Solid-phase synthesis of new pyrrolobenzodiazepine–chalcone conjugates: DNA-binding affinity and anticancer activity

An Update on the synthesis and pharmacological properties of pyrazoles obtained from Chalcone

Abstract:

A review concerning the synthesis and pharmacological properties of pyrazoles obtained from Chalcone described in the literature over the last 5 years (2016-2020) was presented and discussed. Among the synthetic approaches for pyrazoles described so far, the cyclization and acetylation method of α,β-unsaturated chalcones and substituted hydrazine was selected and analyzed. 105 pyrazole derivatives (3-107) were evaluated as well as their pharmacological activities, namely, antineoplastic, anti-inflammatory, antioxidant, antibacterial, antifungal, antimycobacterial, antiplasmodial, Alzheimer's disease, enzymes inhibition (like acetylcholinesterase, carbonic anhydrase, and malonyl CoA decarboxylase), anticonvulsant, among others. Pyrazolic compounds are widely used in the new drugs design with a wide spectrum of pharmacological approaches, therefore, it is relevant to research the synthetic methods and therapeutic properties of different pyrazole derivatives.

Recent advances in multi-component reactions and their mechanistic insights: a triennium review

This review summarizes the recent developments in MCRs, incorporating different strategies along with their mechanistic aspects.

Synthesis and Antimicrobial Activity of Novel 1, 2, 4-Triazolopyrimidofuroquinazolinones from Natural Furochromones (Visnagenone and Khellinone)

BACKGROUND

Previous and recent scientific research has shown that triazolopyrimidine and furochromones have a wide range of pharmacological activities for the treatment of numerous diseases, including anticancer, antiviral, anti-depressant, anti-microbial, anti-inflammatory, and analgesic activities.

OBJECTIVE

Preparation of new drugs derived from a natural furochromones as (1-hydrazinyl or methylthio),-furopyrimidoquinazolinone, 1, 2, 4-triazolopyrimidofuroquinazolin-5-one, and quinazoline- pyrimidofuro- quinazoline-8, 10-dione and the study of their biological activity as antimicrobial agents.

METHODS

A series of novel N'-furopyrimidoquinazoline-hydrazide; 1, 2, 4-triazolopyrimidofuroquinazolin- 5-one; furopyrimidoquinazolin-3-one and quinazoline-pyrimidofuroquinazoline-8, 10- dione derivatives were synthesized from substituted (methylthio)-furopyrimidoquinazolinone (3ab) and 1-hydrazinyl-furopyrimido- quinazolinone (4a-b) as the starting material.

RESULTS

All compounds were synthesized in good yields (71-95%) in a gradually efficient system under mild condition and some of the procedures were used such as microwave oven. The new compounds have been confirmed by means of different spectroscopic methods such as IR, 1D and 2D -NMR techniques and mass spectrum. The in vitro antimicrobial activities were evaluated for the prepared compounds using many types of bacteria (Gram-positive and Gram-negative) and fungi.

CONCLUSION

1, 2, 4-triazolopyrimidofuroquinazolin-5-one derivatives (10a-f, 8a-b, 7a-b and 6a-d) showed the most efficient antimicrobial activities compared with the cefotaxime sodium and nystatin as standard drugs.

Synthesis and catalytic evaluation of PVP-CeO2/rGO as a highly efficient and recyclable heterogeneous catalyst for multicomponent reactions in water

A highly efficient and eco-friendly route for the reduction of graphene oxide (GO) to reduced graphene oxide (rGO) was developed by using polyvinylpyrrolidone coated CeO₂ NPs (PVP-CeO₂) as a reducing and stabilizing agent. The resulting carbonaceous material, PVP-CeO₂/rGO, was well characterized with different spectroscopic techniques such as Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), elemental mapping, Transmission Electron Microscopy (TEM), Raman spectroscopy, powder X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray Photoelectron Spectroscopy (XPS), and Thermal Gravimetric (TG) analyses. The material exhibited high catalytic potential towards multicomponent reactions for the synthesis of biologically relevant benzodiazepine derivatives in aqueous media. The efficiency of the material for the desired reaction was shown in the form of an excellent product yield (96-98%) and a very short reaction time period (7-10 min). The use of water as solvent and recyclability of the catalyst made the present protocol acceptable from a green perspective.

Synthesis of Novel Benzodifuranyl; 1,3,5-Triazines; 1,3,5-Oxadiazepines; and Thiazolopyrimidines Derived from Visnaginone and Khellinone as Anti-Inflammatory and Analgesic Agents

Novel (4-methoxy or 4,8-dimethoxy)-3-methyl-N-(6-oxo-2-thioxo-1,2,3, 6-tetrahydro- pyrimidin-4-yl) benzo [1,2-b: 5, 4-b'] difuran-2-carboxamide (5a-b) has been synthesized by the reaction of visnagenone-ethylacetate (2a) or khellinone-ethylacetate (2b) with 6-aminothiouracil in dimethylformamide or refluxing of benzofuran-oxy-N-(2-thioxopyrimidine) acetamide (4a-b) in sodium ethoxide to give the same products (5a,b) in good yields. Thus, compounds 5a-b are used as an initiative to prepare many new heterocyclic compounds such as 2-(4-(3-methylbenzodifuran- 2-carbox-amido) pyrimidine) acetic acid (6a-b), N-(thiazolo[3, 2-a]pyrimidine)-3-methylbenzo- difuran-2-carboxamide (7a-b), N-(2-thioxopyrimidine)-methylbenzodifuran-2-carbimidoylchloride (8a-b), N-(2-(methyl-thio) pyrimidine)-3-methylbenzodifuran-2-carbimidoylchloride (9a-b), N-(2, 6 -di(piperazine or morpholine)pyrimidine)-1-(3-methylbenzodifuran)-1-(piperazine or morpholine) methanimine(10a-d), 8-(methylbenzodifuran)-thiazolopyrimido[1,6-a][1,3,5]triazine-3,5-dione (11a -b), 8-(3-methyl benzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-trione (12a-b), and 2,10 -di(sub-benzylidene)-8-(3-methylbenzodifuran)-thiazolopyrimido[6,1-d][1,3,5]oxadiazepine-3,5,11- trione (13a-f). All new chemical structures were illustrated on the basis of elemental and spectral analysis (IR, NMR, and MS). The new compounds were screened as cyclooxygenase-1/ cyclooxygenase-2 (COX-1/COX-2) inhibitors and had analgesic and anti-inflammatory activities. The compounds 10a-d and 13a-f had the highest inhibitory activity on COX-2 selectivity, with indices of 99-90, analgesic activity of 51-42% protection, and anti-inflammatory activity of 68%-59%. The inhibition of edema for the same compounds, 10a-d and 13a-f, was compared with sodium diclofenac as a standard drug.

Analgesic and Antioxidant Activities of 4-Phenyl-1,5-benzodiazepin-2-one and Its Long Carbon Chains Derivatives

The aim of this work is to deepen the pharmacological effect of 4-phenyl-1,5-benzodiazepin-2-one derivatives which have a similar structure to nonionic surfactants: 4-phenyl-1,5-benzodiazepin-2-one is the hydrophilic head, and the carbon chain is hydrophobic tail. The antinociceptive activity of 4-phenyl-1,5-benzodiazepin-2-one derivatives was determined using acetic acid-induced writhing and tail immersion tests. In addition, the in vitro antioxidant activities of the tested derivatives were determined by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and ferric reducing power assay. A single oral administration of these compounds at the doses of 50 and 100 mg/kg significantly reduced the number of abdominal writhes induced by acetic acid injection. Acute pretreatment with 4-phenyl-1,5-benzodiazepin-2-one derivatives at the dose of 100 mg/kg caused a significant increase in the tail withdrawal latency in the tail immersion test. Additionally, a significant scavenging activity in DPPH and reducing power was observed in testing antioxidant assays. Finally, we carried out a study of the antioxidant activity of these derivatives. The results of this study reveal that these compounds have a low antioxidant activity compared to the BHT. It decreases with the polarity of the molecule. The present study suggests that 4-phenyl-1,5-benzodiazepin-2-one derivatives possess potent antinociceptive and antioxidant effects, which suggest that the tested compounds may be useful in the treatment of pain and oxidation disorders.

Lacerda EDP, Lima RS, M. de Oliveira A, Camargo AJ, Napolitano HB. Molecular modeling of cytotoxic activity of a new terpenoid-like bischalcone

This study describes the synthesis and structure of (1E,4E)-1-(3-chlorophenyl)-5-(2,6,6-trimethylcyclohex-1-en-1-yl)penta-1,4-dien-3-one (BC I). This work evaluates molecular docking and cytotoxic activity against two tumor cell lines.

Crystal structure and Hirshfeld surface analysis of a new benzodiazepine derivative: 4-di-chloro-methyl-2,3-di-hydro-1H-1,5-benzodiazepin-2-one

In the title compound, C10H8Cl2N2O, the seven-membered diazepine ring adopts a boat-shaped conformation. The mean planes of the two rings of the benzodiazepine unit are inclined to each other by 22.05 (6)°. In the crystal, mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif. The dimers are linked by C-H⋯π inter-actions, forming layers lying parallel to (10). The roles of the inter-molecular inter-actions in the crystal packing were clarified using Hirshfeld surface analysis; the most important contributions are from Cl⋯H/H⋯Cl (30.5%) and H⋯H (22.5%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (4Z)-1-butyl-4-(2-oxo-propyl-idene)-2,3,4,5-tetra-hydro-1H-1,5-benzodiazepin-2-one

The asymmetric unit of the title compound, C16H20N2O2, consists of two independent mol-ecules differing slightly in the conformations of the seven-membered rings and the butyl substituents, where the benzene rings are oriented at a dihedral angle of 34.56 (3)°. In the crystal, pairwise inter-molecular C-H⋯O and complementary intra-molecular C-H⋯O hydrogen bonds form twisted strips extending parallel to (012). These strips are connected into layers parallel to (111) by additional inter-molecular C-H⋯O hydrogen bonds. The layers are further joined by C-H⋯π inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (65.5%), H⋯C/C⋯H (16.0%) and H⋯O/O⋯H (15.8%) inter-actions.

Synthesis of New Furothiazolo Pyrimido Quinazolinones from Visnagenone or Khellinone and Antimicrobial Activity

Substituted-6-methyl-1-thioxo-1,2-dihydro-3H-furo[3,2-g]pyrimido[1,6-a]quinazolin-3-ones (5a,b) were synthesized from condensation of visnagenone (2a) or khellinone (2b) with 6-amino-thiouracil (3) in dimethylformamide or refluxing of (4a) or (4b) in dimethylformamide. Hence, compounds (5a,b) were used as the starting materials for preparing many new heterocyclic compounds such as; furo[3,2-g]pyrimido[1,6-a]quinazoline (6a,b), furo[3,2-g]thiazolo[2',3':2,3]pyrimido[1,6-a]quinazolinone (7a,b), substituted-benzylidene-furo[3,2-g]thiazolo[2',3':2,3]pyrimido[1,6-a]quinazoline-3,5-dione (8a⁻f), 3-oxo-furo[3,2-g]pyrimido[1,6-a]quinazoline-pentane-2,4-dione (9a,b), 1-(pyrazole)-furo[3,2-g]pyrimido[1,6-a]quinazolinone (10a,b), 2-(oxo or thioxo)-pyrimidine-furo[3,2-g]pyrimido[1,6-a]quinazolinone (11a⁻d), 1-(methylthio)-furo[3,2-g]pyrimido[1,6-a]quinazolinone (12a,b), 1-(methyl-sulfonyl)-furo[3,2-g]pyrimido[1,6-a]quinazolinone (13a,b) and 6-methyl-1-((piperazine) or morpholino)-3H-furo[3,2-g]pyrimido[1,6-a]quinazolin-3-one (14a⁻d). The structures of the prepared compounds were elucidated on the basis of spectral data (IR, ¹H-NMR, ¹³C-NMR, MS) and elemental analysis. Antimicrobial activity was evaluated for the synthesized compounds against Gram-positive, Gram-negative bacteria and fungi. The new compounds, furothiazolo pyrimido quinazolines 8a⁻f and 11a⁻d displayed results excellent for growth inhibition of bacteria and fungi.

Chalcone: A Privileged Structure in Medicinal Chemistry

Privileged structures have been widely used as an effective template in medicinal chemistry for drug discovery. Chalcone is a common simple scaffold found in many naturally occurring compounds. Many chalcone derivatives have also been prepared due to their convenient synthesis. These natural products and synthetic compounds have shown numerous interesting biological activities with clinical potentials against various diseases. This review aims to highlight the recent evidence of chalcone as a privileged scaffold in medicinal chemistry. Multiple aspects of chalcone will be summarized herein, including the isolation of novel chalcone derivatives, the development of new synthetic methodologies, the evaluation of their biological properties, and the exploration of the mechanisms of action as well as target identification. This review is expected to be a comprehensive, authoritative, and critical review of the chalcone template to the chemistry community.

1-Ethyl-4-phenyl-1,5-benzodiazepine-2-thione

In the title compound, C17H16N2S, the seven-membered ring adopts a boat conformation. The two aromatic rings are inclined at an angle of 34.7 (1)° to one another. The molecules pack in helical chains running along thec-axis direction through C—H...S hydrogen bonds. These are further linked into layers parallel to (100) by weak C—H...π(ring) interactions. The structure was refined as a two-component inversion twin.

Small hybrid heteroaromatics: resourceful biological tools in cancer research

Nowadays, hybrid drugs containing two or more covalently linked known potential pharmacophores are designed to simultaneously modulate multiple targets of multifactorial diseases to overcome the side effects associated with a single drug.

Synthesis of Benzo[4,5]isoquinolino[2,1-a]Quinazoline Derivatives by Reaction of (Z)-2-amino-N′-arylbenzimidamides with 1,8-naphthalic Anhydride

The reaction of (Z)-2-amino-N′-arylbenzimidamides with 1,8-naphthalic anhydride in ethyl alcohol under reflux conditions gave benzo[4,5] isoquinolino[2,1-a]quinazoline derivatives in good yield.

Synthesis and cytotoxic evaluation of alkoxylated chalcones

A series of chalcones a1–20 bearing a 4-OMe groups on the A-ring were initially synthesized and their anticancer activities towards HepG2 cells evaluated. Subsequently, a series of chalcones b1–42 bearing methoxy groups at the 2' and 6'-positions of the B-ring were synthesized and their anticancer activities towards five human cancer cell lines (HepG2, HeLa, MCF-7, A549 and SW1990) and two non-tumoral human cell lines evaluated. The results showed that six compounds (b6, b8, b11, b16, b18, b22, b23 and b29) displayed promising activities, with compounds b22 and b29 in particular showing higher levels of activity than etoposide against all five cancer cell lines. Compound b29 showed a promising SI value compared with both HMLE and L02 (2.1–6.5 fold in HMLE and > 33 > 103.1 fold in L02, respectively).

Progress of the synthesis of condensed pyrazole derivatives (from 2010 to mid-2013)

Condensed pyrazole derivatives are important heterocyclic compounds due to their excellent biological activities and have been widely applied in pharmaceutical and agromedical fields. In recent years, numerous condensed pyrazole derivatives have been synthesized and advanced to clinic studies with various biological activities. In this review, we summarized the reported synthesis methods of condensed pyrazole derivatives from 2010 until now. All compounds are divided into three parts according to the rings connected to pyrazole-ring, i.e. [5, 5], [5,F 6], and [5, 7]-condensed pyrazole derivatives. The biological activities and applications in pharmaceutical fields are briefly introduced to offer an orientation for the design and synthesis of condensed pyrazole derivatives with good biological activities.

DNA binding, antiviral activities and cytotoxicity of new furochromone and benzofuran derivatives

Bromination of visnagin (1) afforded 9-bromovisnagin (2) which on its alkaline hydrolysis afforded the 3-acetyl benzofuran derivative (3). The condensation of (3) with hydrazine hydrate, phenylhydrazine and/or hydroxylamine hydrochloride afforded the corresponding pyrazole derivatives (4a, b) and isoxazole derivative (4c). On the other hand, when compound 3 was condensed with some aromatic aldehydes, this yielded corresponding α, β-unsaturated keto derivatives (5a-e). Furthermore, when 1 was subjected to chlorosulfonation, the visnaginsulfonylchloride derivative 6 was afforded, which on amidation using morpholine, a sulonamido derivative (7) was obtained. Alkaline hydrolysis of the latter compound yielded 7-N-morpholinosulsamidobenzofuran (8) which was condensed with some aromatic aldehydes to yield the corresponding chalcone compounds (9a-e). Demethylation of visnagin afforded norvisnagin (10). The reaction of 10 with ethylbromoacetate in dry acetone yielded the ester benzopyran derivative (11) which reacted with hydrazine hydrate to afford the corresponding hydrazide derivative (12) and this was condensed with 3,4,5-trimethoxybenzaldehyde to give the corresponding hydrazone (13). A thaizolidinone derivative (14) was obtained by condensation of (13) with thioglycolic acid. Chloromethylation of norvisnagin afforded a 4-chloromethyl derivative (15) which reacted with different primary and secondary amines to yield the corresponding ethylamino derivative (16a, b). Moreover, mannich bases (16a, b) and (17a-c) were obtained by reacting norvisnagin with different primary and secondary amines in the presence of formalin but benzoylation of (16a, b) and (17a-c) afforded 4-oxybenzoyl derivative (18a-e). The prepared compounds were tested for their interaction with DNA; bromovisnagin 2 showed the highest affinity and compounds 6, 15, 8a, > 14, > 16b, 17a, and 16a showed moderate activity in decreasing potency. Moreover, compound 2 also was the most active as antiviral agent toward HS-I virus and compounds 6, 7, 15, 14, 16a, and 18a were found to be moderately active. CD(50) of the active compounds were also measured.

Synthesis of Dibenzo[b,e][1,4]Diazepine Derivatives

The reaction of ( Z)-2-amino- N‘-arylbenzamidines with both 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 2,3,5,6-tetrachloro-1,4-benzoquinone have been studied. The reactions were carried at room temperature overnight in dry ethyl acetate and proceed via a charge transfer complexe to give dibenzo[ b,e][1,4]diazepine derivatives in 35–44% yield. Benzodiazepine derivatives have anti-inflammatory, antiviral, antimicrobial, antileukaemic, antiplatelet, anticonvulsant, antianxiety, antidepressive and antitumour activities. The products were fully characterised according to their spectral analyses.

Recent progress in therapeutic applications of chalcones

INTRODUCTION

Chalcones are a group of plant-derived polyphenolic compounds belonging to the flavonoids family that possess a wide variety of cytoprotective and modulatory functions, which may have therapeutic potential for multiple diseases. Their physicochemical properties seem to define the extent of their biological activity.

AREAS COVERED

A comprehensive synopsis of recent patent literature (2005 - 2011) describing chalcones and their derivatives on selected activities (e.g., anti-inflammatory, antimitotic, cytotoxic, antioxidant, anti-infection) is provided in this paper. Synthesis, combinatorial techniques, biological evaluation in vitro/in vivo, and new biological assays are discussed. In addition to selected biological data, a wide range of pharmaceutical applications and pharmaceutical compositions are also summarized.

EXPERT OPINION

Several natural and synthetic chalcones and their derivatives appear as promising anti-inflammatory and anticancer activities. Their clinical evaluation will be critical to assess their therapeutic utility. Those for which the mechanism of action is well defined can serve as lead compounds for the design of new, more promising molecules.

Synthesis and anticancer activity of chalcone-pyrrolobenzodiazepine conjugates linked via 1,2,3-triazole ring side-armed with alkane spacers

Aiming to develop multitarget drugs for the anticancer treatment, a new class of chalcone-pyrrolo[2,1-c] [1,4]benzodiazepine (PBD) conjugates linked through a 1,2,3-triazole moiety containing alkane spacers has been designed and synthesized. Combining these two core pharmacophore structures with modifications at A-C8/C-C2-position of PBD ring system yielded analogs with improved efficacy and have shown promising in vitro anticancer activity ranging from <0.1-2.92 μM. These PBD-conjugates caused G1 cell cycle arrest with effect on G1 cell cycle regulatory proteins such as Cyclin D1 and Cdk4. These conjugates also exhibited inhibitory effect on NF-kB, Bcl-XL proteins that play a vital role in breast cancer cell proliferation. These findings suggest that one of the compound 4d among this series is most effective and has potential for detailed investigations.

1-(4-Amino-phen-yl)-3-[2-(trifluoro-meth-yl)phen-yl]prop-2-en-1-one

The title compound, C₁₆H₁₂F₃NO, a derivative of biologically active chalcones, comprises two benzene rings and a central –CH=CH—C(=O)– unit. The dihedral angle between the two rings is 10.9 (1)° and the mol­ecule adopts an E configuration about the central olefinic bond. The crystal structure is stabilized by inter­molecular N—H⋯O and N—H⋯N hydrogen bonds.

Synthesis of Benzonaphtho[1,4]Diazepine Derivatives via the Reaction of 2-Aminoarylbenzimidamides with 2,3-Dichloro-1,4-Naphthoquinone

A series of (Z)-13-(arylimino)-12,13-dihydro-5H-benzo[e]naphtho[2,3-b][1,4]diazepine-6,11-dione derivatives have been synthesised by one pot cyclisation in good yield via electron donor–acceptor complexes by reacting 2-aminoarylbenzimidamides with 2,3-dichloro-1,4-naphthoquinone. The high yield and simplified workup procedure in addition to the mild and neutral reaction conditions are the main advantages of this approach.