Use of intensity quotients and differences in absolute structure refinement

First total synthesis of asperilactone B. Revision of absolute stereochemistry of asperilactones B and C

The first total synthesis and absolute configuration assignment of asperilactone B (I) have been accomplished. Additionally, a revision of the absolute stereochemistry of asperilactone C has been done. The first total synthesis of the opposite enantiomer of asperilactone B (ent-I) has also been achieved, as well as that of C-7 epimers of both asperilactones B (8) and C (9).

Sesquiterpene Cyclase BcBOT2 Promotes the Unprecedented Wagner-Meerwein Rearrangement of the Methoxy Group

Presilphiperfolan-8β-ol synthase (BcBOT2), a substrate-promiscuous sesquiterpene cyclase (STC) of fungal origin, is capable of converting two new farnesyl pyrophosphate (FPP) derivatives modified at C7 of farnesyl pyrophosphate (FPP) bearing either a hydroxymethyl group or a methoxymethyl group. These substrates were chosen based on a computationally generated model. Biotransformations yielded five new oxygenated terpenoids. Remarkably, the formation of one of these tricyclic products can only be explained by a cationically induced migration of the methoxy group, presumably via a Meerwein-salt intermediate, unprecedented in synthetic chemistry and biosynthesis. The results show the great principle and general potential of terpene cyclases for mechanistic studies of unusual cation chemistry and for the creation of new terpene skeletons.

Molecular structure and selective theophylline complexation by conformational change of diethyl N,N'-(1,3-phenylene)dicarbamate

The receptor ability of diethyl N,N'-(1,3-phenylene)dicarbamate (1) to form host-guest complexes with theophylline (TEO) and caffeine (CAF) by mechanochemistry was evaluated. The formation of the 1-TEO complex (C12H16N2O4·C7H8N4O2) was preferred and involves the conformational change of one of the ethyl carbamate groups of 1 from the endo conformation to the exo conformation to allow the formation of intermolecular interactions. The formation of an N-H...O=C hydrogen bond between 1 and TEO triggers the conformational change of 1. CAF molecules are unable to form an N-H...O=C hydrogen bond with 1, making the conformational change and, therefore, the formation of the complex impossible. Conformational change and selective binding were monitored by IR spectroscopy, solid-state 13C nuclear magnetic resonance and single-crystal X-ray diffraction. The 1-TEO complex was characterized by IR spectroscopy, solid-state 13C nuclear magnetic resonance, powder X-ray diffraction and single-crystal X-ray diffraction.

Antifungal Pseuboyenes A-J, Bergamotene-Derived Sesquiterpenoids from a Cold-Seep-Derived Pseudallescheria boydii

A chemical investigation of a cold-seep-sediment-derived fungus, Pseudallescheria boydii CS-793, resulted in characterization of 10 novel bergamotene-derived sesquiterpenoids, pseuboyenes A-J (1-10). Their structures were elucidated by spectroscopic and X-ray crystallographic analyses as well as using the modified Mosher's method. Compound 1 represents the first example of a β-bergamotene containing a 6-oxobicyclo[3.2.1]octane nucleus adducted with a methyl lactate unit, while 8-10 involve a skeletal rearrangement from bergamotene. Compounds 2-5 showed significant antifungal activities against Colletotrichum gloeosporioides Penz. and Fusarium oxysporum with MICs ranging from 0.5 to 8 μg/mL. Compound 4 exhibited an in vitro anti-F. proliferatum effect with an EC50 value of 1.0 μg/mL.

Ligandability Assessment of IL-1β by Integrated Hit Identification Approaches

Human interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays a critical role in the regulation of the immune response and the development of various inflammatory diseases. In this publication, we disclose our efforts toward the discovery of IL-1β binders that interfere with IL-1β signaling. To this end, several technologies were used in parallel, including fragment-based screening (FBS), DNA-encoded library (DEL) technology, peptide discovery platform (PDP), and virtual screening. The utilization of distinct technologies resulted in the identification of new chemical entities exploiting three different sites on IL-1β, all of them also inhibiting the interaction with the IL-1R1 receptor. Moreover, we identified lysine 103 of IL-1β as a target residue suitable for the development of covalent, low-molecular-weight IL-1β antagonists.

Hyperatins A-D, highly oxidized polycyclic polyprenylated acylphloroglucinols from Hypericum perforatum L. with hypoglycemic potential in liver cells

Hyperatins A-D (1-4), four previously undescribed polycyclic polyprenylated acylphloroglucinols, were isolated from Hypericum perforatum L. (St. John's wort). Compound 1 possessed a unique octahydroindeno[1,7a-b]oxirene ring system with a rare 2,7-dioxabicyclo[2.2.1]heptane fragment. Compounds 2-4 had an uncommon decahydrospiro[furan-3,7'-indeno[7,1-bc]furan] ring system. Their structures were established by spectroscopic analyses and X-ray crystallography. Plausible biosynthetic pathways of 1-4 were also proposed. Compounds 1 and 2 exerted promising hypoglycemic activity by inhibiting glycogen synthase kinase 3 expression in liver cells.

Crystal structure and Hirshfeld surface analysis of dimethyl 2-oxo-4-(pyridin-2-yl)-6-(thio-phen-2-yl)cyclo-hex-3-ene-1,3-di-carboxyl-ate

In the title compound, C19H17NO5S, the cyclo-hexene ring adopts nearly an envelope conformation. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional network. In addition, C-H⋯π inter-actions connect the mol-ecules by forming layers parallel to the (010) plane. According to the Hirshfeld surface analysis, H⋯H (36.9%), O⋯H/H⋯O (31.0%), C⋯H/H⋯C (18.9%) and S⋯H/H⋯S (7.9%) inter-actions are the most significant contributors to the crystal packing.

Direct Observation of Circularly Polarized Nonlinear Optical Activities in Chiral Hybrid Lead Halides

Circularly polarized light emission is a crucial application in imaging, sensing, and photonics. However, utilizing low-energy photons to excite materials, as opposed to high-energy light excitation, can facilitate deep-tissue imaging and sensing applications. The challenge lies in finding materials capable of directly generating circularly polarized nonlinear optical effects. In this study, we introduce a chiral hybrid lead halide (CHLH) material system, R/S-DPEDPb3Br8·H2O (DPED = 1,2-diphenylethylenediammonium), which can directly produce circularly polarized second harmonic generation (CP-SHG) through linearly polarized infrared light excitation, exhibiting a polarization efficiency as high as 37% at room temperature. To understand the spin relaxation mechanisms behind the high polarization efficiency, we utilized two models, so-called D'yakonov-Perel' (DP) and Bir-Aronov-Pikus (BAP) mechanisms. The unique zigzag inorganic frameworks within the hybrid structure are believed to reduce the dielectric confinement and exciton binding energy, thus enhancing spin polarization, especially in regions with a high excitation pump fluence based on the DP mechanism. In the case of low excitation pump fluence, the BAP mechanism dominates, as evidenced by the observed decrease in the polarization ratio from CP-SHG measurement. Using density functional theory analysis, we elucidate how the distinctive 8-coordination environment of lead bromide building blocks effectively suppresses spin-orbit coupling at the conduction band minimum. This suppression significantly diminishes spin-splitting, thereby slowing the spin relaxation rate.

Absolute structure determination of Berkecoumarin by X-ray and electron diffraction

X-ray and electron diffraction methods independently identify the S-enantiomer of Berkecoumarin [systematic name: (S)-8-hydroxy-3-(2-hydroxypropyl)-6-methoxy-2H-chromen-2-one]. Isolated from Berkeley Pit Lake Penicillium sp., Berkecoumarin is a natural product with a light-atom composition (C13H14O5) that challenges in-house absolute structure determination by anomalous scattering. This study further demonstrates the utility of dynamical refinement of electron-diffraction data for absolute structure determination.

(S)-2-Carb-oxy-ethyl l-cysteinyl sulfone

The title compound {systematic name: (2S)-2-aza-niumyl-3-[(2-carb-oxy-ethane)-sulfon-yl]propano-ate}, C6H11NO6S, forms enanti-opure crystals in the monoclinic space group P21 and exists as a zwitterion, with a protonated α-amino group and a deprotonated α-carboxyl group. Both the carboxyl groups and the amino group are involved in an extensive multicentered inter-molecular hydrogen-bonding scheme. In the crystal, the diperiodic network of hydrogen bonds propagates parallel to (101) and involves inter-connected heterodromic R 4 3(10) rings. Electrostatic forces are major contributors to the structure energy, which was estimated by DFT calculations as E total = -333.5 kJ mol-1.

Tetra-kis(2,4,6-tri-methyl-anilido)tin(IV)

Transamination of Sn(NMe2)4 with H2NMes (Mes is 2,4,6-tri-methyl-phenyl, C9H11) led to the formation of the title compound, [Sn(C9H12N)4] or Sn(NHMes)4, which crystallizes in the tetra-gonal space group P 21 c, with four formula units per unit cell. The mol-ecular structure consists of a central tin(IV) atom, which is surrounded by four NHMes groups. Sn(NHMes)4 possesses crystallographically imposed symmetry. The SnN4 coordination polyhedron is best described as a compressed bis-phenoid.

En Route to a Molecular Terminal Tin Oxide

In the pursuit of terminal tin chalcogenides, heteroleptic stannylenes bearing terphenyl- and hexamethyldisilazide ligands were reacted with carbodiimides to yield the respective guanidinato complexes. Further supported by quantum chemical calculations, this revealed that the iso-propyl-substituted derivative provides the maximum steric protection achievable. Oxidation with elemental selenium produced monomeric terminal tin selenides with four-coordinate tin centers. In reactions with N2O as oxygen transfer reagent, silyl migration toward putative terminal tin oxide intermediates gave rise to tin complexes with terminal ─OSiMe3 functionality. To prevent silyl migration, the silyl groups were substituted with cyclohexyl moieties. This analogue exhibited distinctively different reactivities toward selenium and N2O, yielding a 1,2,3,4,5-tetraselenastannolane and chalcogenide-bridged dimeric compounds, respectively.

NIBR-LTSi is a selective LATS kinase inhibitor activating YAP signaling and expanding tissue stem cells in vitro and in vivo

The YAP/Hippo pathway is an organ growth and size regulation rheostat safeguarding multiple tissue stem cell compartments. LATS kinases phosphorylate and thereby inactivate YAP, thus representing a potential direct drug target for promoting tissue regeneration. Here, we report the identification and characterization of the selective small-molecule LATS kinase inhibitor NIBR-LTSi. NIBR-LTSi activates YAP signaling, shows good oral bioavailability, and expands organoids derived from several mouse and human tissues. In tissue stem cells, NIBR-LTSi promotes proliferation, maintains stemness, and blocks differentiation in vitro and in vivo. NIBR-LTSi accelerates liver regeneration following extended hepatectomy in mice. However, increased proliferation and cell dedifferentiation in multiple organs prevent prolonged systemic LATS inhibition, thus limiting potential therapeutic benefit. Together, we report a selective LATS kinase inhibitor agonizing YAP signaling and promoting tissue regeneration in vitro and in vivo, enabling future research on the regenerative potential of the YAP/Hippo pathway.

Crystal structure, intermolecular interactions, charge-density distribution and ADME properties of the acridinium 4-nitrobenzoate and 2-amino-3-methylpyridinium 4-nitrobenzoate salts: a combined experimental and theoretical study

Acridines are a class of bioactive agents which exhibit high biological stability and the ability to intercalate with DNA; they have a wide range of applications. Pyridine derivatives have a wide range of biological activities. To enhance the properties of acridine and 2-amino-3-methylpyridine as the active pharmaceutical ingredient (API), 4-nitrobenzoic acid was chosen as a coformer. In the present study, a mixture of acridine and 4-nitrobenzoic acid forms the salt acridinium 4-nitrobenzoate, C13H10N+·C7H4NO4- (I), whereas a mixture of 2-amino-3-methylpyridine and 4-nitrobenzoic acid forms the salt 2-amino-3-methylpyridinium 4-nitrobenzoate, C6H9N2+·C7H4NO4- (II). In both salts, protonation takes place at the ring N atom. The crystal structure of both salts is predominantly governed by hydrogen-bond interactions. In salt I, C-H...O and N-H...O interactions form an infinite chain in the crystal, whereas in salt II, intermolecular N-H...O interactions form an eight-membered R22(8) ring motif. A theoretical charge-density analysis reveals the charge-density distribution of the inter- and intramolecular interactions of both salts. An in-silico ADME analysis predicts the druglikeness properties of both salts and the results confirm that both salts are potential drug candidates with good bioavailability scores and there is no violation of the Lipinski rules, which supports the druglikeness properties of both salts. However, although both salts exhibit drug-like properties, salt I has higher gastrointestinal absorption than salt II and hence it may be considered a potential drug candidate.

Curvularin derivatives from the marine mangrove derived fungus Penicillium sumatrense MA-325

Sumalarins D-G (1-4), four previously undescribed curvularin derivatives, along with two known related metabolites, curvularin (5) and dehydrocurvularin (6), were isolated and identified from the mangrove-derived fungus Penicillium sumatrense MA-325. Among them, sumalarin D (1) represents a unique example of curvularin derivative featuring a 5-methylfuran-2-yl-methyl group. Their structures were elucidated based on analysis of NMR and MS data as well as comparison of ECD spectra and quantum chemical calculations of NMR, and compound 1 was confirmed by X-ray crystallographic analysis. Compounds 1, 2, 5, and 6 are active against aquatic pathogenic bacteria Vibrio alginolyticus and V. harveyi with MIC values ranging from 4 to 64 μg/mL, while compound 6 is cytotoxic against tumor cell lines 5673, HCT 116, 786-O, and Hela with IC50 values of 3.5, 10.6, 10.9, and 14.9 μM, respectively.

Metal-metal cooperativity boosts Lewis basicity and reduction properties of the bis(gallanediyl) CyL2Ga2

The interplay of two proximate gallium centres equips the bimetallic complex CyL2Ga2 (1, CyL2 = 1,2-trans-Cy[NC(Me)C(H)C(Me)N(Dip)]2, Dip = 2,6-i-Pr2C6H3) with increased Lewis basicity and higher reducing power compared to the monometallic gallanediyl LGa (2, L = HC[MeCN(Dip)]2) as evidenced by cross-over experiments. Quantum chemical calculations were employed to support the experimental findings.

Optically Pure Calixarenyl Phosphine via Stereospecific Alkylation on Evans' Oxazolidinone Moiety

A convenient protocol for the synthesis of 25,26,27-tribenzoyl-28-[((S)-1-diphenylphos- phanyl-propan-2-yl)oxy]-calix[4]arene via stereospecific methylation on Evans' oxazolidinone moiety was reported. According to the 13C NMR analysis of this phosphine, the calix[4]arene skeleton adopted a 1,3-alternate conformation. The latter conformation of the macrocycle and the (S)-chirality of the carbon atom bearing the methyl substituent were confirmed by a single-crystal X-ray diffraction study. After coordination of the phosphinated ligand to the dimeric [RuCl2(p-cymene)]2 organometallic precursor, the resulting arene-ruthenium complex was tested in the asymmetric reduction of acetophenone and alcohol was obtained with modest enantiomeric excess.

Synthesis and crystal structure of a silver(I) 6-methylmercaptopurine riboside complex

Silver nitrate reacts with 6-methylmercaptopurine riboside (6-MMPR) in aqueous solution containing methanol and dimethyl sulfoxide at room temperature to give a colourless crystalline complex, namely, bis(6-methylmercaptopurine riboside-κN7)(nitrato-κ2O,O')silver(I) 2.32-hydrate, [Ag(NO3)(C11H14N4O4S)2]·2.32H2O. The crystal structure, determined from synchrotron diffraction data, shows a central AgI ion on a crystallographic twofold rotation axis, coordinated in an almost linear fashion by two 6-MMPR ligands via atom N7 (purine numbering), with the nitrate counter-ion loosely coordinated as a bidentate ligand, forming a discrete molecular complex as an approximate dihydrate. The complex and water molecules are connected in a three-dimensional network by hydrogen bonding.

2-Ferrocenyl-2-[(2-ferrocenylethen-yl)(morpholin-4-yl)meth-yl]-1,3-di-thiol-ane

The mol-ecular structure of 2-ferrocenyl-2-[(2-ferrocenylethen-yl)(morpholin-4-yl)meth-yl]-1,3-di-thiol-ane, [Fe2(C5H5)2(C19H21NOS2)] or C29H31Fe2NOS2, has the ferrocenyl fragments in a trans disposition with respect to the vinyl group. One of the methyl-ene groups is disordered over two sites with occupancies of 0.782 (13):0.218 (13). In the crystal, cyclo-penta-dienyl-C-H⋯O(morpholin-yl) inter-actions feature within helical chains parallel to the c-axis direction. The chains are connected by methyl-ene- and cyclo-penta-dienyl-C-H⋯O(cyclo-penta-dien-yl) inter-actions.

Crystal structure and Hirshfeld surface analysis of 4,4'-di-meth-oxy-biphenyl-3,3',5,5'-tetra-carb-oxy-lic acid dihydrate

In the crystal of the title compound, C18H14O10·2H2O, the arene rings of the biphenyl moiety are tilted at an angle of 24.3 (1)°, while the planes passing through the carboxyl groups are rotated at angles of 8.6 (1) and 7.7 (1)° out of the plane of the benzene ring to which they are attached. The crystal structure is essentially stabilized by O-H⋯O bonds. Here, the carboxyl groups of neighbouring host mol-ecules are connected by cyclic R 2 2(8) synthons, leading to the formation of a three-dimensional network. The water mol-ecules in turn form helical supra-molecular strands running in the direction of the crystallographic c-axis (chain-like water clusters). The second H atom of each water mol-ecule provides a link to a meth-oxy O atom of the host mol-ecule. A Hirshfeld surface analysis was performed to qu-antify the contributions of the different inter-molecular inter-actions, indicating that the most important contributions to the crystal packing are from H⋯O/O⋯H (37.0%), H⋯H (26.3%), H⋯C/C⋯H (18.5%) and C⋯O/O⋯C (9.5%) inter-actions.

Crystal structure, Hirshfeld surface analysis, calculations of crystal voids, inter-action energy and energy frameworks as well as density functional theory (DFT) calculations of 3-[2-(morpholin-4-yl)eth-yl]-5,5-di-phenyl-imidazolidine-2,4-dione

In the title mol-ecule, C21H23N3O3, the imidazolidine ring slightly deviates from planarity and the morpholine ring exhibits the chair conformation. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds form helical chains of mol-ecules extending parallel to the c axis that are connected by C-H⋯π(ring) inter-actions. A Hirshfeld surface analysis reveals that the most important contributions for the crystal packing are from H⋯H (55.2%), H⋯C/C⋯H (22.6%) and H⋯O/O⋯H (20.5%) inter-actions. The volume of the crystal voids and the percentage of free space were calculated to be 236.78 Å3 and 12.71%, respectively. Evaluation of the electrostatic, dispersion and total energy frameworks indicates that the stabilization is dominated by the nearly equal electrostatic and dispersion energy contributions. The DFT-optimized mol-ecular structure at the B3LYP/6-311 G(d,p) level is compared with the experimentally determined mol-ecular structure in the solid state. Moreover, the HOMO-LUMO behaviour was elucidated to determine the energy gap.

Crystal structure of (S)-5-(3-acetyl-5-chloro-2-ethoxy-6-fluorophenyl)-2-oxazolidinone

The structure of (S)-5-(3-acetyl-5-chloro-2-ethoxy-6-fluorophenyl)-2-oxazolidinone, C13H13ClFNO4, at 100 K has monoclinic (P21) symmetry. The compound has a polymeric structure propagated by a screw axis parallel to the b axis with N-H⋯O hydrogen bonding. It is of inter-est with respect to efforts in the synthesis of a candidate anti-cancer drug, parsaclisib.

Crystal structures of sulfonamide protected bicyclic guanidines: (S)-8-{[(tert-butyl-dimethyl-sil-yl)-oxy]meth-yl}-1-[(2,2,4,6,7-penta-methyl-2,3-di-hydro-benzo-furan-5-yl)sulfon-yl]-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium tri-fluoro-methane-sulfonate and (S)-8-(iodo-meth-yl)-1-tosyl-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium iodide

Two compounds, (S)-8-{[(tert-butyl-dimethyl-sil-yl)-oxy]meth-yl}-1-[(2,2,4,6,7-penta-methyl-2,3-di-hydro-benzo-furan-5-yl)sulfon-yl]-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium tri-fluoro-methane-sulfonate, C27H46N3O4SSi+·CF3O3S-, (1) and (S)-8-(iodo-meth-yl)-1-tosyl-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium iodide, C15H21IN3O2S+·I-, (2), have been synthesized and characterized. They are bicyclic guanidinium salts and were synthesized from N-(tert-but-oxy-carbon-yl)-l-me-thio-nine (Boc-l-Met-OH). The guanidine is protected by a 2,2,4,6,7-penta-methyl-dihydro-benzo-furan-5-sulfonyl (Pbf, 1) or a tosyl (2) group. In the crystals of both compounds, the guanidinium group is almost planar and the N-H forms an intra-molecular hydrogen bond in a six-membered ring to the oxygen atom of the sulfonamide protecting group.

Synthesis and crystal structures of bis-[1-oxopyridin-2-olato(1-)]bis-(penta-fluoro-phen-yl)silicon(IV)-tetra-hydro-furan-pentane (2/1/1), bis-[1-oxopyridin-2-olato(1-)]bis-(p-tol-yl)silicon(IV), and dimesitylbis[1-oxopyridin-2-olato(1-)]silicon(IV)

The neutral organosilicon(IV) complex, (C6F5)2Si(OPO)2 (OPO = 1-oxopyridin-2-one, C5H4NO2), was synthesized from (C6F5)2Si(OCH3)2 and 2 equiv. of 1-hy-droxy-pyridin-2-one in tetra-hydro-furan (THF). Single crystals grown from the diffusion of n-pentane into a THF solution were identified as a THF hemisolvate and an n-pentane hemisolvate, (C6F5)2Si(OPO)2·0.5THF·0.5C5H12 (1). p-Tol-yl2Si(OPO)2 (2) and mesit-yl2Si(OPO)2 (3) crystallized directly from reaction mixtures of 2 equiv. of Me3Si(OPO) with p-tol-yl2SiCl2 and mesit-yl2SiCl2, respectively, in aceto-nitrile. The oxygen-bonded carbon and nitro-gen atoms of the OPO ligands in 1, 2, and 3 were modeled as disordered indicating co-crystallization of up to three possible diastereomers in each. Solution NMR studies support the presence of exclusively the all-cis isomer in 1 and multiple isomers in 2. Poor solubility of 3 limited its characterization in solution.

Pseudallenes A and B, new sulfur-containing ovalicin sesquiterpenoid derivatives with antimicrobial activity from the deep-sea cold seep sediment-derived fungus Pseudallescheria boydii CS-793

Pseudallenes A and B (1 and 2), the new and rare examples of sulfur-containing ovalicin derivatives, along with three known analogues 3-5, were isolated and identified from the culture extract of Pseudallescheria boydii CS-793, a fungus obtained from the deep-sea cold seep sediments. Their structures were established by detailed interpretation of NMR spectroscopic and mass spectrometric data. X-ray crystallographic analysis confirmed and established the structures and absolute configurations of compounds 1-3, thus providing the first characterized crystal structure of an ovalicin-type sesquiterpenoid. In the antimicrobial assays, compounds 1-3 showed broad-spectrum inhibitory activities against several plant pathogens with MIC values ranging from 2 to 16 μg/mL.

(+)-Cedrol hemihydrate: a natural product derived from drying eastern red cedar (Juniperus virginiana) wood

Cedrol-like compounds are of pharmacological interest due to their diverse range of medicinal effects and are used globally in traditional medicines and cosmetics. Many cedrol tautomers are known from molecular studies but few have been studied in crystalline form by X-ray diffraction. Acicular white crystals collected from the wood of eastern red cedar (Juniperus virginiana) are determined to be (+)-cedrol hemihydrate, namely, (1S,2R,5S,7R,8R)-2,6,6,8-tetramethyltricyclo[5.3.1.01,5]undecan-8-ol hemihydrate, C15H26O·0.5H2O, a novel packing of two unique cedrol molecules (Z' = 2) with a single water molecule [space group P212121; a = 6.1956 (1), b = 14.5363 (1), and c = 30.9294 (4) Å]. The hydrogen bonding forms a one-dimensional spiral chain running along the a axis, following the chirality of the cedrol molecule, through hydrogen-bonding interactions with a right-handed helical configuration in graph-set notation Δ-C33(6) > a > c > b. The crystal packing and symmetry are different from crystalline isocedrol due to the different hydrogen-bonding geometry.

High-throughput nanoscale crystallization of dihydropyridine active pharmaceutical ingredients

Single-crystal X-ray diffraction analysis of small molecule active pharmaceutical ingredients is a key technique in the confirmation of molecular connectivity, including absolute stereochemistry, as well as the solid-state form. However, accessing single crystals suitable for X-ray diffraction analysis of an active pharmaceutical ingredient can be experimentally laborious, especially considering the potential for multiple solid-state forms (solvates, hydrates and polymorphs). In recent years, methods for the exploration of experimental crystallization space of small molecules have undergone a `step-change', resulting in new high-throughput techniques becoming available. Here, the application of high-throughput encapsulated nanodroplet crystallization to a series of six dihydropyridines, calcium channel blockers used in the treatment of hypertension related diseases, is described. This approach allowed 288 individual crystallization experiments to be performed in parallel on each molecule, resulting in rapid access to crystals and subsequent crystal structures for all six dihydropyridines, as well as revealing a new solvate polymorph of nifedipine (1,4-dioxane solvate) and the first known solvate of nimodipine (DMSO solvate). This work further demonstrates the power of modern high-throughput crystallization methods in the exploration of the solid-state landscape of active pharmaceutical ingredients to facilitate crystal form discovery and structural analysis by single-crystal X-ray diffraction.

CP, Mendoza Á, Hernández Téllez G. (S)-(+)-1-(4-Bromo-phen-yl)-N-[(4-methoxyphen-yl)methyl-idene]ethyl-amine and bis-{(S)-(+)-1-(4-bromo-phen-yl)-N-[(4-methoxyphen-yl)methyl-idene]ethyl-amine-κN}di-chlorido-palladium(II)

The (S)-(+)-1-(4-bromo-phen-yl)-N-[(4-methoxyphen-yl)methyl-idene]ethyl-amine ligand, C16H16BrNO, (I), was synthesized through the reaction of 4-meth-oxy-anisaldehyde with (S)-(-)-1-(4-bromo-phen-yl)ethyl-amine. It crystallizes in the ortho-rhom-bic space group P212121 belonging to the Sohncke group, featuring a single mol-ecule in the asymmetric unit. The refinement converged successfully, achieving an R factor of 0.0508. The PdII com-plex bis-{(S)-(+)-1-(4-bromo-phen-yl)-N-[(4-methoxyphen-yl)methyl-idene]ethyl-amine-κN}di-chlorido-pal-ladium(II), [PdCl2(C16H16BrNO)2], (II), crystallizes in the monoclinic space group P21 belonging to the Sohncke group, with two mol-ecules in the asymmetric unit. The central atom is tetra-coordinated by two N atoms and two Cl atoms, resulting in a square-planar configuration. The imine moieties exhibit a trans configuration around the PdII centre, with average Cl-Pd-N angles of approximately 89.95 and 90°. The average distances within the palladium com-plex for the two mol-ecules are ∼2.031 Å for Pd-N and ∼2.309 Å for Pd-Cl.

1-Ethyl-3,3-di-methyl-spiro-[indoline-2,8'-phenaleno[1,9-fg]chromene]

The title pyrene-fused spiro-pyran derivative, C30H25NO, crystallizes with two mol-ecules in the asymmetric unit with dihedral angles between their fused-ring sub units of 76.20 (8) and 89.38 (9)°. In the crystal, weak C-H⋯π inter-actions link the mol-ecules into a three-dimensional network.

Synthesis and crystal structure of [1,3-bis-(2,6-diiso-propyl-phen-yl)imidazol-2-yl-idene](iso-cyanato-κN)gold(I)

The title complex, [Au(NCO)(C27H36N2)], was synthesized by ligand metathesis from [1,3-bis-(2,6-diiso-propyl-phen-yl)imidazol-2-yl-idene]gold(I) chloride and sodium cyanate in anhydrous tetra-hydro-furan and crystallized from toluene at 233 K in the ortho-rhom-bic space group P212121, as a neutral complex with the central Au atom di-coordinated by an N-heterocyclic carbene [Au-C = 1.963 (2) Å] and an iso-cyanate [Au-N 1.999 (2) Å] ligands, with a linear CAuNCO moiety. The crystal packing is consolidated by C-H⋯O hydrogen bonds.

Crystal structures of the alkali aluminoboracites A4B4Al3O12Cl (A = Li, Na)

Single crystals of alkali aluminoboracites, A 4B4Al3O12Cl (A = Li, Na), were grown using the self-flux method, and their isotypic cubic crystal structures were determined by single-crystal X-ray diffraction. Na4B4Al3O12Cl is the first reported sodium boracite, and its lattice parameter [13.5904 (1) Å] is the largest among the boracites consisting of a cation-oxygen framework reported so far. For both crystals, structure models refined in the cubic space group F 3c, which assume that all cubic octant subcells in the unit cell are equivalent, converged with R1 factors of ∼0.03. However, the presence of weak hhl reflections with odd h and l values indicates that refinements in the space group F23, which presume a checkerboard-like ordering of two types of subcells with slightly different atomic positions, are more appropriate.

Synthesis and crystal structure of N1,N2-di-methyl-ethane-dihydrazide

The title compound, N 1,N 2-di-methyl-ethane-dihydrazide, C4H10N4O2, was obtained by the methyl-ation of oxalyl dihydrazide protected with phthalimide. The mol-ecule is essentially non-planar with a dihedral angle between the two planar hydrazide fragments of 86.5 (2)°. This geometry contributes to the formation of a multi-contact three-dimensional supra-molecular network via C-H⋯O, N-H⋯O and N-H⋯N hydrogen bonds.

Cadmium phosphates Cd2(PO4)OH and Cd5(PO4)2(OH)4 crystallizing in mineral structures

Single crystals of two basic cadmium phosphates, dicadmium orthophosphate hydroxide, Cd2(PO4)OH, and penta-cadmium bis-(orthophosphate) tetra-kis-(hydroxide), Cd5(PO4)2(OH)4, were obtained under hydro-thermal conditions. Cd2(PO4)OH adopts the triplite [(Mn,Fe)2(PO4)F] structure type. Its asymmetric unit comprises two Cd, one P and five O sites, all situated at the general Wyckoff position 8 f of space group I2/a; two of the O atoms are positionally disordered over two sites, and the H atom could not be localized. Disregarding the disorder, distorted [CdO6] polyhedra form a tri-periodic network by edge-sharing with neighbouring [CdO6] units and by vertex-sharing with [PO4] units. The site associated with the OH group is coordinated by four Cd atoms in a distorted tetra-hedral manner forming 1 ∞[(OH)Cd4/2] chains parallel to [001]. The oxygen environment around the OH site suggests multiple acceptor atoms for possible O-H⋯O hydrogen-bonding inter-actions and is the putative reason for the disorder. Cd5(PO4)2(OH)4 adopts the arsenoclasite [Mn5(AsO4)2(OH)4] structure type. Its asymmetric unit comprises five Cd, two P, and twelve O sites all located at the general Wyckoff position 4 a of space group P212121; the H atoms could not be localized. The crystal structure of Cd5(PO4)2(OH)4 can be subdivided into two main sub-units. One consists of three edge-sharing [CdO6] octa-hedra, and the other of two edge- and vertex-sharing [CdO6] octa-hedra. Each sub-unit forms corrugated ribbons extending parallel to [100]. The two types of ribbons are linked into the tri-periodic arrangement through vertex-sharing and through common [PO4] tetra-hedra. Qu-anti-tative structure comparisons are made with isotypic M 5(XO4)2(OH)4 crystal structures (M = Cd, Mn, Co; X = P, As, V).

Synthesis and crystal structures of boryl ortho-silylaryl tri-fluoro-methane-sulfonates

We report the synthesis and structural characterization of three crystalline borylated ortho-silylaryl tri-fluoro-methane-sulfonates: 5-(4,4,5,5-tetra-methyl-1,3,2-dioxaborolan-2-yl)-2-(tri-methyl-sil-yl)phenyl tri-fluoro-methane-sulfonate, C16H24BF3O5SSi (1a), 4-(4,4,5,5-tetra-methyl-1,3,2-dioxaborolan-2-yl)-2-(tri-methyl-sil-yl)phenyl tri-fluoro-methane-sulfonate, C16H24BF3O5SSi (1b), and 2-methyl-4-(4,4,5,5-tetra-methyl-1,3,2-dioxaborolan-2-yl)-6-(tri-methyl-silyl)phen-yl tri-fluoro-methane-sulfonate, C17H26BF3O5SSi (2), which are versatile aryne precursors. For all three compounds, the heteroatom substituents are almost coplanar with the central aromatic moiety. C-heteroatom bonding metrics are unexceptional and fall withing the typical range of C-B, C-Si, and C-O single bonds. Despite numerous electronegative sites, only weak inter-molecular inter-actions are observed in the solid state.

Synthesis, crystal structure and thermal properties of di-bromido-bis-(2-methyl-pyridine N-oxide-κO)cobalt(II)

Reaction of CoBr2 with 2-methyl-pyridine N-oxide in n-butanol leads to the formation of the title compound, [CoBr2(C6H7NO)2] or [CoBr2(2-methyl-pyridine N-oxide)2]. Its asymmetric unit consists of one CoII cation as well as two bromide anions and two 2-methyl-pyridine N-oxide coligands in general positions. The CoII cations are tetra-hedrally coordinated by two bromide anions and two 2-methyl-pyridine N-oxides, forming discrete complexes. In the crystal structure, these complexes are linked predominantly by weak C-H⋯Br hydrogen bonding into chains that propagate along the crystallographic a-axis. Powder X-ray diffraction (PXRD) measurements indicate that a pure phase was obtained. Thermoanalytical investigations prove that the title compound melts before decomposition; before melting, a further endothermic signal of unknown origin was observed that does not correspond to a phase transition.

α-D-2'-Deoxyadenosine, an irradiation product of canonical DNA and a component of anomeric nucleic acids: crystal structure, packing and Hirshfeld surface analysis

α-D-2'-Deoxyribonucleosides are products of the γ-irradiation of DNA under oxygen-free conditions and are constituents of anomeric DNA. They are not found as natural building blocks of canonical DNA. Reports on their conformational properties are limited. Herein, the single-crystal X-ray structure of α-D-2'-deoxyadenosine (α-dA), C10H13N5O3, and its conformational parameters were determined. In the crystalline state, α-dA forms two conformers in the asymmetric unit which are connected by hydrogen bonds. The sugar moiety of each conformer is arranged in a `clamp'-like fashion with respect to the other conformer, forming hydrogen bonds to its nucleobase and sugar residue. For both conformers, a syn conformation of the nucleobase with respect to the sugar moiety was found. This is contrary to the anti conformation usually preferred by α-nucleosides. The sugar conformation of both conformers is C2'-endo, and the 5'-hydroxyl groups are in a +sc orientation, probably due to the hydrogen bonds formed by the conformers. The formation of the supramolecular assembly of α-dA is controlled by hydrogen bonding and stacking interactions, which was verified by a Hirshfeld and curvedness surface analysis. Chains of hydrogen-bonded nucleobases extend parallel to the b direction and are linked to equivalent chains by hydrogen bonds involving the sugar moieties to form a sheet. A comparison of the solid-state structures of the anomeric 2'-deoxyadenosines revealed significant differences of their conformational parameters.

Crystal structure, Hirshfeld surface analysis and energy frameworks of 1-[(E)-2-(2-fluoro-phen-yl)diazan-1-yl-idene]naphthalen-2(1H)-one

The title compound, C16H11N2OF, is a member of the azo dye family. The dihedral angle subtended by the benzene ring and the naphthalene ring system measures 18.75 (7)°, indicating that the compound is not perfectly planar. An intra-molecular N-H⋯O hydrogen bond occurs between the imino and carbonyl groups. In the crystal, the mol-ecules are linked into inversion dimers by C-H⋯O inter-actions. Aromatic π-π stacking between the naphthalene ring systems lead to the formation of chains along [001]. A Hirshfeld surface analysis was undertaken to investigate and qu-antify the inter-molecular inter-actions. In addition, energy frameworks were used to examine the cooperative effect of these inter-molecular inter-actions across the crystal, showing dispersion energy to be the most influential factor in the crystal organization of the compound.

Prop-2-ynyl 3-meth-oxy-4-(prop-2-yn-yloxy)benzoate

The title compound, C14H12O4, comprises of two crystallographically independent mol-ecules in the asymmetric unit, linked via C-H⋯O inter-actions to form dimeric entities. The allylic groups are twisted out of the phenyl planes with dihedral angles varying between 7.92 (13) and 25.42 (8)°. In the crystal, the packing follows a zigzag pattern along the c-axis direction. The absolute configuration of the sample could not be determined reliably.

Discovery of highly functionalized grayanane diterpenoids from the flowers of Rhododendron molle as potent analgesics

A systematical investigation on the chemical constituents of the flowers of Rhododendron molle (Ericaceae) led to the isolation and characterization of thirty-eight highly functionalized grayanane diterpenoids (1-38), including twelve novel analogues molleblossomins A-L (1-12). Their structures were elucidated by comprehensive methods, including 1D and 2D NMR analysis, calculated ECD, 13C NMR calculations with DP4+ probability analysis, and single crystal X-ray diffraction. Molleblossomins A (1), B (2), and E (5) are the first representatives of 2β,3β:9β,10β-diepoxygrayanane, 2,3-epoxygrayan-9(11)-ene, and 5,9-epoxygrayan-1(10),2(3)-diene diterpenoids, respectively. Molleblossomins G (7) and H (8) represent the first examples of 1,3-dioxolane-grayanane conjugates furnished with the acetaldehyde and 4-hydroxylbenzylidene acetal moieties, respectively. All grayanane diterpenoids 1-38 were screened for their analgesic activities in the acetic acid-induced writhing model, and all of them exhibited significant analgesic activities. Diterpenoids 6, 13, 14, 17, 20, and 25 showed more potent analgesic effects than morphine at a lower dose of 0.2 mg/kg, with the inhibition rates of 51.4%, 68.2%, 94.1%, 66.9%, 97.7%, and 60.0%, respectively. More importantly, even at the lowest dose of 0.04 mg/kg, rhodomollein X (14), rhodojaponin VI (20), and rhodojaponin VII (22) still significantly reduced the number of writhes in the acetic acid-induced pain model with the percentages of 61.7%, 85.8%, and 64.6%, respectively. The structure-activity relationship was summarized and might provide some hints to design novel analgesics based on the functionalized grayanane diterpenoids.

trans-Di-chlorido-bis-[(S)-(-)-1-(4-methyl-phen-yl)ethyl-amine-κN]palladium(II)

The title complex, [PdCl2(C9H13N)2], comprises a single mol-ecule in the asymmetric unit. The PdII atom is tetra-coordinated by two N atoms from two trans-aligned organic ligands and two Cl ligands, forming a square-planar metal coordination environment. The distances from the ortho-H atoms on the phenyl ring to the central PdII atom fall within the range 4.70-5.30 Å, precluding any significant intra-molecular Pd⋯H inter-actions.

Bis(2-hy-droxy-2,3-di-hydro-1H-inden-1-aminium) tetra-chlorido-palladate(II) hemihydrate

A new square-planar palladium complex salt hydrate, (C9H12NO)2[PdCl4]·0.5H2O, has been characterized. The asymmetric unit of the complex salt comprises two [PdCl4]2- dianions, four 2-hy-droxy-2,3-di-hydro-1H-inden-1-aminium cations, each derived from (1R,2S)-(+)-1-amino-indan-2-ol, and one water mol-ecule of crystallization. In the crystal, a two-dimensional layer parallel to (001) features a number of O-H⋯O, N-H⋯O, O-H⋯Cl and N-H⋯Cl hydrogen bonds.

Crystal structure and Hirshfeld surface analysis of 3-benzyl-2-[bis(1H-pyrrol-2-yl)methyl]thiophene

In the title compound, C20H18N2S, the asymmetric unit comprises two similar mol-ecules (A and B). In mol-ecule A, the central thio-phene ring makes dihedral angles of 89.96 (12) and 57.39 (13)° with the 1H-pyrrole rings, which are bent at 83.22 (14)° relative to each other, and makes an angle of 85.98 (11)° with the phenyl ring. In mol-ecule B, the corresponding dihedral angles are 89.49 (13), 54.64 (12)°, 83.62 (14)° and 85.67 (11)°, respectively. In the crystal, mol-ecular pairs are bonded to each other by N-H⋯N inter-actions. N-H⋯π and C-H⋯π inter-actions further connect the mol-ecules, forming a three-dimensional network. A Hirshfeld surface analysis indicates that H⋯H (57.1% for mol-ecule A; 57.3% for mol-ecule B), C⋯H/H⋯C (30.7% for mol-ecules A and B) and S⋯H/H⋯S (6.2% for mol-ecule A; 6.4% for mol-ecule B) inter-actions are the most important contributors to the crystal packing.

X-ray crystallographic structure of a novel enantiopure chiral isothiourea with potential applications in enantioselective synthesis

The synthesis of a chiral isothiourea, namely, (4aR,8aR)-3-phenyl-4a,5,6,7,8,8a-hexahydrobenzo[4,5]imidazo[2,1-b]thiazol-9-ium bromide, C15H17N2S+·Br-, with potential organocatalytic and anti-inflammatory activity is reported. The preparation of the heterocycle of interest was carried out in two high-yielding steps. The hydrobromide salt of the isothiourea of interest provided suitable crystals for X-ray diffraction analysis, the results of which are reported. Salient observations from this analysis are the near perpendicular arrangement of the phenyl ring and the mean plane of the heterocycle. This conformational characteristic may be relevant with regard the stereoselectivity induced by the chiral isothiourea in asymmetric reactions. Furthermore, evidence was found for the existence of an S...Br- halogen bond.

(4-Butyl-1-ethyl-1,2,4-triazol-5-yl-idene)[(1,2,5,6-η)-cyclo-octa-1,5-diene](tri-phenyl-phosphane)rhodium(I) tetra-fluorido-borate

In the title triazole-based N-heterocyclic carbene rhodium(I) cationic complex with a tetra-fluorido-borate counter-anion, [Rh(C8H12)(C8H15N3)(C18H15P)]BF4, which crystallizes with two cations and two anions in the asymmetric unit, the Rh center has a distorted square-planar coordination geometry with expected bond distances. Several nonclassical C-H⋯F hydrogen-bonding inter-actions help to consolidate the packing. Two of the F atoms of one of the anions are disordered over adjacent sites in a 0.814 (4):0.186 (4) ratio.

Synthesis, crystal structure and properties of chlorido-tetra-kis-(pyridine-3-carbo-nitrile)-thio-cyanato-iron(II)

Reaction of FeCl2·4H2O with KSCN and 3-cyano-pyridine (pyridine-3-carbo-nitrile) in ethanol accidentally leads to the formation of single crystals of Fe(NCS)(Cl)(3-cyano-pyridine)4 or [FeCl(NCS)(C6H4N2)4]. The asymmetric unit of this compound consists of one FeII cation, one chloride and one thio-cyanate anion that are located on a fourfold rotation axis as well as of one 3-cyano-pyridine coligand in a general position. The FeII cations are sixfold coordinated by one chloride anion and one terminally N-bonding thio-cyanate anion in trans-positions and four 3-cyano-pyridine coligands that coordinate via the pyridine N atom to the FeII cations. The complexes are arranged in columns with the chloride anions, with the thio-cyanate anions always oriented in the same direction, which shows the non-centrosymmetry of this structure. No pronounced inter-molecular inter-actions are observed between the complexes. Initially, FeCl2 and KSCN were reacted in a 1:2 ratio, which lead to a sample that contains the title compound as the major phase together with a small amount of an unknown crystalline phase, as proven by powder X-ray diffraction (PXRD). If FeCl2 and KSCN is reacted in a 1:1 ratio, the title compound is obtained as a nearly pure phase. IR investigations reveal that the CN stretching vibration for the thio-cyanate anion is observed at 2074 cm-1, and that of the cyano group at 2238 cm-1, which also proves that the anionic ligands are only terminally bonded and that the cyano group is not involved in the metal coordination. Measurements with thermogravimetry and differential thermoanalysis reveal that the title compound decomposes at 169°C when heated at a rate of 4°C min-1 and that the 3-cyano-pyridine ligands are emitted in two separate poorly resolved steps. After the first step, an inter-mediate compound with the composition Fe(NCS)(Cl)(3-cyano-pyridine)2 of unknown structure is formed, for which the CN stretching vibration of the thio-cyanate anion is observed at 2025 cm-1, whereas the CN stretching vibration of the cyano group remain constant. This strongly indicates that the FeII cations are linked by μ-1,3-bridg-ing thio-cyanate anions into chains or layers.

Resolution by diastereomeric salts: Access to both enantiomers of racemic acid using the same enantiomer of resolving base

Racemic carboxylic acid, a Diels-Alder cycloadduct derived from 5-bromo-3-phenyl-α-pyrone and acrylate dienophile, was resolved into enantiomers by diastereomeric salt crystallization. Quinidine was used as a sole resolving base. The salt of (+)-acid crystallized from aqueous acetonitrile solution. Once this salt was separated by filtration, quinidine salt with (-)-acid crystallized from mother liquor. As a result, both enantiomers of Diels-Alder cycloadduct were isolated in high enantiomeric purity.

Synthesis, characterization, crystal structure and Hirshfeld surface analysis of isobutyl 4-[4-(di-fluoro-meth-oxy)phen-yl]-2,6,6-trimethyl-5-oxo-1,4,5,6,7,8-hexa-hydro-quinoline-3-carboxyl-ate

In the title compound, C24H29F2NO4, which crystallizes in the ortho-rhom-bic Pca21 space group with Z = 4, the 1,4-di-hydro-pyridine ring adopts a distorted boat conformation, while the cyclo-hexene ring is in a distorted half-chair conformation. In the crystal, the mol-ecules are linked by N-H⋯O and C-H⋯O inter-actions, forming supra-molecular chains parallel to the a axis. These chains pack with C-H⋯π inter-actions between them, forming layers parallel to the (010) plane. The cohesion of the crystal structure is ensured by van der Waals inter-actions between these layers. Hirshfeld surface analysis shows the major contributions to the crystal packing are from H⋯H (56.9%), F⋯H/H⋯F (15.7%), O⋯H/H⋯O (13.7%) and C⋯H/H⋯C (9.5%) contacts.

Three previously undescribed metabolites from Cordyceps cicadae JXCH-1, an entomopathogenic fungus

Three previously undescribed compounds, cordycicadione (1), cordycicadin F (2), and 7-hydroxybassiatin (3), were isolated from the cultures of Cordyceps cicadae JXCH1, an entomopathogenic fungus. Their structures and relative configurations were elucidated primarily by NMR spectroscopic analysis. The absolute configurations of 1 and 2 were determined by ECD calculations. Single-crystal X-ray diffraction method was adopted to determine the absolute configuration of 3. Compound 2 is a polycyclic polyketide with an unusual enol ether moiety and a spiro ring. The compounds obtained in this study were subjected to screening their inhibition against the proliferation of the human lung cancer cell line A549 and the production of nitric oxide in murine macrophages RAW264.7.

Host-guest system of a phosphorylated macrocycle assisting structure determination of oily molecules in single-crystal form

X-ray crystallography is the most reliable method for structure elucidation and absolute configuration determination of organic molecules based on their single-crystal forms. However, many analytes are hard to crystallize because of their low melting points (an oily state at room temperature) or conformational flexibility. Here, we report the crystallization of a macrocycle, CTX[P(O)Ph] (host), which is a cyclotrixylohydroquinoylene (CTX) derivative, with 26 oily organic molecules (guests), which is applied for the structural determination of the guest with X-ray crystallography. With the aid of the host, CTX[P(O)Ph], the guest molecules were well-ordered with full occupancy in crystal structures. In most cases, at least one guest structure without any disorder could be observed; solvent masking was not necessary for the single crystal X-ray structural analysis, and thus the structures of the guests could be successfully determined, and the absolute configuration could be assigned reliably for chiral guests with this method. The crystallization mechanism was further discussed from theoretical and experimental perspectives, suggesting that the negative electrostatic potential surface of CTX[P(O)Ph] and noncovalent interactions between the host and guest were crucial for the ordered arrangements of the guest.

Design, Synthesis, and Biological Evaluation of Novel Camphor-Based Hydrazide and Sulfonamide Derivatives as Laccase Inhibitors against Plant Pathogenic Fungi/Oomycetes

To discover novel natural product-based fungicidal agrochemicals, 41 novel camphanic acid hydrazide and camphor sulfonamide derivatives were designed, synthesized, and tested for their antifungal profile against four plant pathogenic fungi and three oomycetes. As a result, some derivatives presented pronounced inhibitory activities toward Botryosphaeria dothidea, Fusarium graminearum, Phytophthora capsici, and Phytophthora nicotianae. Especially, compound 4b demonstrated the most potent anti-B. dothidea activity (EC50 = 1.28 mg/L), much stronger than positive control chlorthalonil. The in vivo assay showed that 4b displayed significant protective and curative effects on apple fruits infected by B. dothidea. The primary antifungal mechanism study revealed that 4b could obviously enhance the cell membrane permeability, destroy the mycelial surface morphology and the cell ultrastructure, and reduce the ergosterol and exopolysaccharide contents of B. dothidea. Further, 4b showed potent laccase inhibitory activity in vitro with an IC50 value of 11.3 μM, superior to positive control cysteine. The molecular docking study revealed that 4b could dock well into the active site of laccase by forming multiple interactions with the key residues in the pocket. The acute oral toxicity test in rats presented that 4b had slight toxicity with an LD50 value of 849.1 mg/kg bw (95% confidence limit: 403.9-1785.3 mg/kg bw). This research identified that the camphanic acid hydrazide derivatives could be promising leads for the development of novel laccase-targeting fungicides.