150950-00-8Relevant articles and documents
Nocapyrones: α- and γ-pyrones from a marine-derived Nocardiopsis sp
Kim, Youngju,Ogura, Hiromu,Akasaka, Kazuaki,Oikawa, Tsutomu,Matsuura, Nobuyasu,Imada, Chiaki,Yasuda, Hisato,Igarashi, Yasuhiro
, p. 4110 - 4125 (2014)
One new α-pyrone (nocapyrone R (1)), and three known γ-pyrones (nocapyrones B, H and L (2-4)) were isolated from the culture extract of a Nocardiopsis strain collected from marine sediment. Structures of these compounds were determined on the basis of spectroscopic data including NMR and MS. γ-Pyrones 2-4 were found to induce adiponectin production in murine ST-13 preadipocyte cells but the α-pyrone 1 had no activity. The absolute configuration of the anteiso-methyl branching in 4 was determined by HPLC comparison of a degraded product of 4 with standard samples as a 2:3 enantiomeric mixture of (R)- and (S)-isomers.
Synthesis and Bioactivity Investigation of the Individual Components of Cyclic Lipopeptide Antibiotics
Cui, A-Long,Hu, Xin-Xin,Gao, Yan,Jin, Jie,Yi, Hong,Wang, Xiu-Kun,Nie, Tong-Ying,Chen, Yang,He, Qi-Yang,Guo, Hui-Fang,Jiang, Jian-Dong,You, Xue-Fu,Li, Zhuo-Rong
, p. 1845 - 1857 (2018)
In this paper, 26 natural polymyxin components and a new derivative S2 were synthesized, and their differences in efficacy and toxicity have been investigated. Almost all of the synthesized components showed strong activity against both susceptible and resistant strains of E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii. The toxicities were obviously different between the components. Only some of the components were tested for toxicity in vivo. Compounds E2, E2-Val, A2, M2, D2, and S2 showed obviously lower renal cytotoxicity and acute toxicity than polymyxins B and E. The in vivo nephrotoxicity of E2, M2, and S2 was similar to that of polymyxin E. Compound S2, with four positive charges, was especially interesting as it possessed both increased efficacy and decreased toxicity. The SAR and toxicity studies indicated that further structural modification could concentrate on polymyxin S. The results also indicated that S2 could be a new drug candidate.
A Highly Convergent Total Synthesis of Leustroducsin B
Trost, Barry M.,Biannic, Berenger,Brindle, Cheyenne S.,O'Keefe, B. Michael,Hunter, Thomas J.,Ngai, Ming-Yu
, p. 11594 - 11597 (2015/09/28)
Leustroducsin B exhibits a large variety of biological activities and unique structural features. An efficient and highly convergent total synthesis of Leustroducsin B was achieved in 17 longest linear and 39 total steps by disconnecting the molecule into three fragments having similar levels of complexity. These pieces were connected via a highly efficient chelate-controlled addition of a vinyl zincate to an α-hydroxy ketone and a silicon-mediated cross-coupling. The stereochemistry of the central and western fragments was set catalytically in high yields and excellent de by a zinc-ProPhenol-catalyzed aldol reaction and a palladium-catalyzed asymmetric allylic alkylation.
