@article {46625, title = {Approach to nigericin derivatives and their therapeutic potential}, journal = {RSC Advances}, volume = {10}, year = {2020}, month = {NOV }, pages = {43085-43091}, type = {Article}, abstract = {

A new nigericin analogue that has been chemically modified was synthesized through a fluorination process from the parent nigericin, produced from a novel Streptomyces strain DASNCL-29. Fermentation strategies were designed for the optimised production of nigericin molecule and subjected for purification and structural analysis. The fermentation process resulted in the highest yield of nigericin (33\% (w/w)). Initially, nigericin produced from the strain DASNCL-29 demonstrated polymorphism in its crystal structure, i.e., monoclinic and orthorhombic crystal lattices when crystallised with methanol and hexane, respectively. Furthermore, nigericin produced has been subjected to chemical modification by fluorination to enhance its efficacy. Two fluorinated analogues revealed that they possess a very potent antibacterial activity against Gram positive and Gram negative bacteria. To date, the nigericin molecule has not been reported for any reaction against Gram-negative bacteria, which are increasingly becoming resistant to antibiotics. For the first time, fluorinated analogues of nigericin have shown promising activity. In vitro cytotoxicity analysis of fluorinated analogues demonstrated tenfold lesser toxicity than the parent nigericin. This is the first type of study where the fluorinated analogues of nigericin showed very encouraging activity against Gram-negative organisms; moreover, they can be used as a candidate for treating many serious infections.

}, doi = {10.1039/d0ra05137c}, author = {Sahu, Amit Kumar and Said, Madhukar S. and Hingamire, Tejashri and Gaur, Megha and Khan, Abujunaid and Shanmugam, Dhanasekaran and Barvkar, Vitthal T. and Dharne, Mahesh S. and Bharde, Atul A. and Dastager, Syed G.} } @article {46795, title = {Total synthesis of (-)-2-methoxy-2-butenolide-3-cinnamate and its antimicrobial potentials}, journal = {Natural Product Research}, year = {2020}, month = {JUL}, type = {Article; Early Access 2020}, abstract = {

The first total synthesis of (-)-2-methoxy-2-butenolide-3-cinnamate (butenolide cinnamate) was achieved using commercially available starting material. The synthesized compound was found to have promising antibacterial activity against Gram-negative strainsEscherichia coli(ATCC 8739),Salmonella typhimurium(ATCC 23564) andPseudomonas aeruginosa(ATCC 19154) with a minimum inhibitory concentration of 2.0 mu g/mL, 1.0 mu g/mL and 2.0 mu g/mL, respectively. Notably, the compound was more potent against Gram-negative test strains than the Gram-positive test strains.

}, keywords = {antibacterial activity, butenolide cinnamate, Total synthesis}, issn = {1478-6419}, doi = {10.1080/14786419.2020.1789979, Early Access Date = JUL 2020}, author = {Said, Madhukar S. and Udavant, Rohini and Sahu, Amit Kumar and Khan, Abujunaid and Nayak, Rashmi and Dastager, Syed G. and Kumar, Pradeep and Gajbhiye, Jayant} } @article {48114, title = {Enceleamycins A-C, furo-naphthoquinones from amycolatopsis sp. MCC0218: isolation, structure elucidation, and antimicrobial activity}, journal = {Journal of Natural Products}, volume = {85}, year = {2022}, month = {MAY}, pages = {1267-1273}, type = {Article}, abstract = {

Three novel furo-naphthoquinones, enceleamycins A-C (1-3), and a new N-hydroxypyrazinone acid (4) were identified from the strain Amycolatopsis sp. MCC 0218, isolated from a soil sample collected from the Western Ghats of India. Their chemical structure and absolute and relative configurations were established by 1D and 2D NMR spectroscopy, single-crystal X-ray crystallography, and high-resolution mass spectrometry. Compounds 1 and 3 were active against methicillin-susceptible and -resistant Staphylococcus aureus with MIC values of 2-16 mu g/mL.

}, issn = {0163-3864}, doi = {10.1021/acs.jnatprod.1c01160}, author = {Khan, Abujunaid and Said, Madhukar S. and Borade, Balasaheb R. and Gonnade, Rajesh and Barvkar, Vitthal and Kontham, Ravindar and Dastager, Syed G.} }