A new mild PTSA-catalyzed method for sulfate ester hydrolysis and acid-catalyzed rearrangement of 12-acetyl-diene-11-ol tetracyclic triterpenoids involving an angular methyl migration

Integracides: Tetracyclic Triterpenoids from Fusarium sp.-Their 5-Lipoxygenase Inhibitory Potential and Structure-Activity Relation Using In Vitro and Molecular Docking Studies

Inflammation is a complicated disorder that is produced as a result of consecutive processes. 5-LOX (5-lipoxygenase) is accountable for various inflammation mediators and leukotrienes synthesis, and its inhibition is the target of anti-inflammation therapeutics. Fungi have acquired enormous attentiveness because of their capability to biosynthesize novel bio-metabolites that reveal diversified bio-activities. A new tetracyclic triterpenoid, integracide L (1), along with integracides B (2) and F (3), were separated from Mentha longifolia-associated Fusarium sp. (FS No. MAR2014). Their structures were verified utilizing varied spectral analyses. The isolated metabolites (1-3), alongside the earlier reported integracides G (4), H (5), and J (6), were inspected for 5-LOX inhibition capacity. Interestingly, 1-6 possessed marked 5-LOX inhibition potentials with IC₅₀s ranging from 1.18 to 3.97 μM compared to zileuton (IC₅₀ 1.17 µM). Additionally, molecular docking was executed to examine the interaction among these metabolites and 5-LOX, as well as to validate the in vitro findings. The docking study revealed their inhibitory activity interactions in the binding pocket. These findings highlighted the potential of integracides as lead metabolites for anti-inflammation drug discovery.

Integracides H-J: New tetracyclic triterpenoids from the endophytic fungus Fusarium sp

Three new tetracyclic triterpenoids namely, integracides H (1), I (4), and J (5), along with integracides B (3) and F (2) have been isolated from the endophytic fungus Fusarium sp. isolated from the roots of Mentha longifolia L. (Labiatae) growing in Saudi Arabia. The structure elucidation of the isolated compounds was achieved by spectroscopic analysis including UV, IR, 1D ((1)H and (13)C) and 2D ((1)H(1)H COSY, TOCSY, HSQC, HMBC, and NOESY) NMR as well as HRESIMS and comparison with literature data. Integracides H (1) and J (5) showed significant anti-leishmanial activity towards Leishmania donovani with IC50 values of 4.75 and 3.29μM, respectively compared to pentamidine (IC50 6.35μM). Moreover, they displayed potent cytotoxic activity towards BT-549, SKOV-3, and KB cell lines with IC50 values of 1.82, 1.32, and 0.18μM and 2.46, 3.01, and 2.54μM, respectively.

Jasisoquinolines A and B, architecturally new isoquinolines, from a marine sponge Jaspis sp

Two architecturally new isoquinolines, jasisoquinolines A and B, were isolated from a marine sponge Jaspis sp. as cathepsin B inhibitors. Their structures were determined by a combination of spectroscopic analyses and chemical methods. Both jasisoquinolines A and B inhibit cathepsin B with an IC(50) value of 10 μg/mL.

Yaku'amides A and B, cytotoxic linear peptides rich in dehydroamino acids from the marine sponge Ceratopsion sp

Two cytotoxic peptides, yaku'amides A (1) and B (2), were isolated from the marine sponge Ceratopsion sp. Their planar structures were elucidated on the basis of spectroscopic data, whereas the absolute configurations were determined by a combination of the Marfey's analysis and dansylation analysis of the total and partial acid hydrolysis products. The growth inhibitory profile of yaku'amide A against a panel of 39 human cancer cell lines was clearly unique and distinguished from other anticancer drugs.

Structures and absolute configurations of sulfate-conjugated triterpenoids including an antifungal chemical defense of the green macroalga Tydemania expeditionis

Cytotoxicity-guided fractionation of the green macroalga Tydemania expeditionis led to isolation of four sulfate-conjugated triterpenoids including one new lanostane-type triterpenoid disulfate, lanosta-8-en-3,29-diol-23-oxo-3,29-disodium sulfate (1), and three known cycloartane-type triterpenoid disulfates, cycloartan-3,29-diol-23-one 3,29-disodium sulfate (2), cycloart-24-en-3,29-diol-23-one 3,29-disodium sulfate (3), and cycloartan-3,23,29-triol 3,29-disodium sulfate (4). Extensive 1D and 2D NMR analyses in combination with X-ray crystallography established the structure and absolute configuration of 1 and allowed determination of the absolute configurations of 2-4 with a revision of previously assigned configuration at C-5. Each natural product was moderately cytotoxic in tumor cell and invertebrate toxicity assays. Of the natural products, only 4 exhibited significant antifungal activity at whole-tissue natural concentrations against the marine pathogen Lindra thalassiae. Comparison of the biological activities of natural products with their desulfated derivatives indicated that sulfation does not appear to confer cytotoxicity or antifungal activity.

Structures of new amphidinols with truncated polyhydroxyl chain and their membrane-permeabilizing activities

Two new homologues of amphidinols (AM14 and AM15) were isolated from the cultured dinoflagellate Amphidinium klebsii. The structures were elucidated on the basis of 2D NMR and collision-induced dissociation MS/MS and turned out to be closely related homologues of AM7. Their weak membrane-disrupting activity indicates that the hydrophobic polyene chain is essential for the potent biological activities. Structure-activity relationship for the polyhydroxyl part was then examined with use of AM homologues possessing various chain lengths, indicating that the pore size of the channel/lesion formed by AMs was not greatly affected by the length of the polyhydroxyl chain.

Integracides: tetracyclic triterpenoid inhibitors of HIV-1 integrase produced by Fusarium sp

HIV-1 integrase is a critical enzyme in the replication of HIV-1. It is absent in the host cells and therefore is a good target for treatment of HIV-1 infections. Integracides are members of the tetracyclic triterpenoids family that were isolated from the fermentation broth of a Fusarium sp. Integracide A, a sulfated ester, exhibited significant inhibitory activity against strand transfer reaction of HIV-1 integrase. The discovery, structure elucidation including single crystal X-ray structure and HIV-1 inhibitory activity of these compounds are described.