Biotransformation of metenolone acetate and epiandrosterone by fungi and evaluation of resulting metabolites for aromatase inhibition.

The present study describes the microbial transformation of anabolic drugs, metenolone acetate (1), and epiandrosterone (6). Three new metabolites, 6ß,17ß-dihydroxy-1-methyl-3-oxo-5α-androst-1-en (2), 5α,15α-dihydroxy-1-methyl-3-oxo-1-en-17-yl acetate (3), 15ß-hydroxy-1-methyl-3-oxo-5α-androst-1,4-dien-17-yl acetate (4), and a known metabolite, 17ß-hydroxy-1-methyl-4-androstadiene-3-one (5) were obtained by biotransformation of metenolone acetate (1) via Trametes hirsuta mushroom. Metabolites 7, and 8 were obtained from the incubation of epiandrosterone (6) with Cunninghamella blakesleeana. While bioconversion of compound 6 with Aspergillus alliaceus yielded seven known metabolites 9-15. Modern spectroscopic techniques were employed for the structure elucidation of biotransformed products. All compounds were evaluated for their aromatase inhibitory activity. Among them, new metabolite 3 exhibited a significant human placental aromatase activity with an IC50 = 19.602 ± 0.47 µM, as compared to standard anti-cancer drug exemestane (IC50 = 0.232 ± 0.031 µM), whereas, metabolite 5 (IC50 = 0.0049 ± 0.0032 µM) exhibited a very potent activity. While substrate 6, and metabolites 2, 7, and 9 were found inactive. Aromatase plays a key role in the biosynthesis of estrogen hormone, responsible for cancer cell proliferation. Its inhibition is therefore targeted for the treatment of ER + breast cancer. Further structural modifications (lead optimization) of compound 3 can lead to more potent aromatase inhibition for possible treatment of ER + breast cancer.

Synthesis of 2-Aminopyrimidine Derivatives and Their Evaluation as ß-Glucuronidase Inhibitors: In Vitro and In Silico Studies.

Currently the discovery and development of potent ß-glucuronidase inhibitors is an active area of research due to the observation that increased activity of this enzyme is associated with many pathological conditions, such as colon cancer, renal diseases, and infections of the urinary tract. In this study, twenty-seven 2-aminopyrimidine derivatives 1-27 were synthesized by fusion of 2-amino-4,6-dichloropyrimidine with a variety of amines in the presence of triethylamine without using any solvent and catalyst, in good to excellent yields. All synthesized compounds were characterized by EI-MS, HREI-MS and NMR spectroscopy. Compounds 1-27 were then evaluated for their ß-glucuronidase inhibitory activity, and among them, compound 24 (IC50 = 2.8 ± 0.10 µM) showed an activity much superior to standard D-saccharic acid 1,4-lactone (IC50 = 45.75 ± 2.16 µM). To predict the binding mode of the substrate and ß-glucuronidase, in silico study was performed. Conclusively, this study has identified a potent ß-glucuronidase inhibitor that deserves to be further studied for the development of pharmaceutical products.

Bioinformatics: A rational combine approach used for the identification and in-vitro activity evaluation of potent ß-Glucuronidase inhibitors.

Identification of hotspot drug-receptor interactions through in-silico prediction methods (Pharmacophore mapping, virtual screening, 3DQSAR, etc), is considered as a key approach in drug designing and development process. In the current design study, advanced in-silico based computational techniques were used for the identification of lead-like molecules against the targeted receptor ß-glucuronidase. The binding pattern of a potent inhibitor in the ligand-receptor X-ray co-crystallize complex was used to identify and extract the structure-base Pharmacophore features. Based on these observations; five structure-based pharmacophore models were derived to conduct the virtual screening of ICCBS in-house data-base. Top-ranked identified Hits (33 compounds) were selected to subject for in-vitro biological activity evaluation against ß-glucuronidase enzyme; out of them, twenty compounds (61% of screened compounds) evaluated as actives, however eleven compounds were found to have significantly higher inhibitory activity, including compounds 1, 5-8, 10, 12-13, and 17-19 with IC50 values ranging from 1.2 µM to 34.9 µM. Out of the eleven potent inhibitors, seven compounds 1, 5, 6, 7, 8, 13, and 19 were found new, and evaluated first time for the ß-glucuronidase inhibitory activity. Compounds 1, 5 and 19 exhibited a highly potent inhibition in uM of ß-glucuronidase enzyme with non-cytotoxic behavior against the mouse fibroblast (3T3) cell line. Our combined in-silico and in-vitro results revealed that the binding pattern analysis of the eleven potent inhibitors, showed almost similar non-covalent interactions, as observed in case of our validated pharmacophore model. The obtained results thus demonstrated that the virtual screening minimizes false positives, and provide a template for the identification and development of new and more potent ß-glucuronidase inhibitors with non-toxic effects.

Synthesis of pyrimidine-2,4,6-trione derivatives: Anti-oxidant, anti-cancer, α-glucosidase, ß-glucuronidase inhibition and their molecular docking studies.

This paper describes a facile protocol, efficient, and environmentally benign for the synthesis a series of barbiturate acid substituted at C5 position 3a-o. The desired compounds subjected in vitro for different set of bioassays including against anti-oxidant (DPPH and super oxide scavenger assays), anti-cancer, α-glucosidase and ß-glucuronidase inhibitions. Compound 3m (IC50=22.9±0.5µM) found to be potent α-glucosidase enzyme inhibitors and showed more activity than standard acarbose (IC50=841±1.73µM). Compound 3f (IC50=86.9±4.33µM) found to be moderate ß-Glucuronidase enzyme inhibitors and showed activity comparatively less than the standard d-saccharic acid 1,4-lactone (IC50=45.75±2.16µM). Furthermore, in sillico investigation was carried out to investigate bonding mode of barbiturate acid derivatives.

Synthesis and ß-glucuronidase inhibitory activity of 2-arylquinazolin-4(3H)-ones.

2-Arylquinazolin-4(3H)-ones 1-25 were synthesized by reacting anthranilamide with various benzaldehydes using CuCl2·2H2O as a catalyst in ethanol under reflux. Synthetic 2-arylquinazolin-4(3H)-ones 1-25 were evaluated for their ß-glucuronidase inhibitory potential. A trend of inhibition IC50 against the enzyme in the range of 0.6-198.2µM, was observed and compared with the standard d-saccharic acid 1,4-lactone (IC50=45.75±2.16µM). Compounds 13, 19, 4, 12, 14, 22, 23, 25, 15, 8, 17, 11, 21, 1, 3, 18, 9, 2, and 24 with the IC50 values within the range of 0.6-44.0µM, indicated that the compounds have superior activity than the standard. The compounds showed no cytotoxic effects against PC-3 cells. A structure-activity relationship is established.

ß-glucuronidase inhibitory studies on coumarin derivatives.

Twenty-three (23) derivatives of coumarin (5-27) were synthesized and screened for their in vitro ß- glucuronidase (E. coli) inhibitory activities. Only three compounds, 7,8-dihydroxy-4-methyl-2H-chromen-2-one (9) (IC50 = 52.39 ± 1.85 µM), 3-chloro-6-hexyl-7-hydroxy-4-methyl-2H-chromen-2-one (18) (IC50 = 60.50 ± 0.87 µM), and 3,6- dichloro-7-hydroxy-4-methyl-2H-chromen-2-one (15) (IC50 = 380.26 ± 0.92 µM) displayed activities against ß- glucuronidase as compared to standard D-saccharic acid 1,4-lactone (IC50 = 45.75 ± 2.16 µM). The results indicated that the activity of the synthetic coumarins depends upon the substituents present on the coumarin skeleton.