Tyrosyl-DNA phosphodiesterase 1 (Tdp1) is an important DNA repair enzyme in humans, and a current and promising inhibition target for the development of new chemosensitizing agents due to its ability to remove DNA damage caused by topoisomerase 1 (Top1) poisons such as topotecan and irinotecan. Herein, we report our work on the synthesis and characterization of new Tdp1 inhibitors that combine the arylcoumarin (neoflavonoid) and monoterpenoid moieties. Our results showed that they are potent Tdp1 inhibitors with IC values in the submicromolar range.
View Article and Find Full Text PDFThe molecular chaperone heat shock protein 90 (Hsp90) is a current inhibition target for the treatment of diseases, including cancer. In humans, there are two major cytosolic isoforms of Hsp90 (Hsp90α and Hsp90β). Hsp90α is inducible and Hsp90β is constitutively expressed.
View Article and Find Full Text PDFTyrosyl-DNA phosphodiesterase 1 (Tdp1) is a promising therapeutic target in cancer therapy. Combination chemotherapy using Tdp1 inhibitors as a component can potentially improve therapeutic response to many chemotherapeutic regimes. A new set of usnic acid derivatives with hydrazonothiazole pharmacophore moieties were synthesized and evaluated as Tdp1 inhibitors.
View Article and Find Full Text PDFExploration of microbial dynamics of Streptomyces lavendulae ACR-DA1, a psychrotrophic isolate from the North-Western Himalayan cold desert, was carried out using matrix-assisted laser desorbtion ionisation-time of flight mass spectrometer. Valinomycin was found as a major produce and cyclic depsipeptide montanastatin as a minor produce. The yield of the valinomycin was found to be 0.
View Article and Find Full Text PDFBackground And Objective: The DNA repair enzyme tyrosyl-DNA-phosphodiesterase 1 (TDP1) is a current inhibition target to improve the efficacy of cancer chemotherapy. Previous studies showed that compounds combining adamantane and monoterpenoid fragments are active against TDP1 enzyme. This investigation is focused on the synthesis of monoterpenoid derived esters of 1-adamantane carboxylic acid as TDP1 inhibitors.
View Article and Find Full Text PDFPresent study relates to the effect of valproic acid, an epigenetic modifier on the metabolic profile of Aspergillus fumigatus (GA-L7), an endophytic fungus isolated from Grewia asiatica L. Seven secondary metabolites were isolated from A. fumigatus (GA-L7) which were identified as: pseurotin A, pseurotin D, pseurotin F2, fumagillin, tryprostatin C, gliotoxin and bis(methylthio)gliotoxin.
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