4307-98-6Relevant articles and documents
Diels-Alder Cycloaddition of Azepino[4,5-b]indoles Towards Hydrocarbazole Derivatives and Related Heterocycles
Cheng, Maosheng,Li, Xiang,Lin, Bin,Liu, Yongxiang,Ma, Jun,Sun, Lei,Xie, Fukai,Xu, Liangyu,Zhang, Bo
supporting information, (2022/01/26)
An approach to hydrocarbazoles bearing an all-carbon quaternary center at C4a position was developed via a Br?nsted acid-initiated Diels-Alder cycloaddition/retro-aza-Michael addition cascade process from azepino[4,5-b]indoles and commercially available d
Tryptamine derivatives disarm colistin resistance in polymyxin-resistant gram-negative bacteria
Barker, William T.,Chandler, Courtney E.,Melander, Roberta J.,Ernst, Robert K.,Melander, Christian
, p. 1776 - 1788 (2019/03/21)
The last three decades have seen a dwindling number of novel antibiotic classes approved for clinical use and a concurrent increase in levels of antibiotic resistance, necessitating alternative methods to combat the rise of multi-drug resistant bacteria. A promising strategy employs antibiotic adjuvants, non-toxic molecules that disarm antibiotic resistance. When co-dosed with antibiotics, these compounds restore antibiotic efficacy in drug-resistant strains. Herein we identify derivatives of tryptamine, a ubiquitous biochemical scaffold containing an indole ring system, capable of disarming colistin resistance in the Gram-negative bacterial pathogens Acinetobacter baumannii, Klebsiella pneumoniae, and Escherichia coli while having no inherent bacterial toxicity. Resistance was overcome in strains carrying endogenous chromosomally-encoded colistin resistance machinery, as well as resistance conferred by the mobile colistin resistance-1 (mcr-1) plasmid-borne gene. These compounds restore a colistin minimum inhibitory concentration (MIC) below the Clinical & Laboratory Sciences Institute (CLSI) breakpoint in all resistant strains.
Ynesulfonamide-Based Silica Gel and Alumina-Mediated Diastereoselective Cascade Cyclizations to Spiro[indoline-3,3′-pyrrolidin]-2-ones under Neat Conditions
Wang, Yanshi,Wang, Xiaoyu,Lin, Jingsheng,Yao, Bo,Wang, Guanghui,Zhao, Yuandong,Zhang, Xinhang,Lin, Bin,Liu, Yang,Cheng, Maosheng,Liu, Yongxiang
supporting information, p. 1483 - 1492 (2018/03/01)
The spiro[indoline-3,3′-pyrrolidin]-2-ones were synthesized via a silica gel and alumina-mediated sequential transformation based on tryptamine-derived ynesulfonamide substrates under neat conditions. The inherent tendency of C?C bond migration through Wagner-Meerwein rearrangement in the synthesis of spirooxindole was prevented by water trapping to the spiroindoleninium intermediate. The functional group tolerances of the methodology were investigated using a variety of substrates. The detailed mechanism of the sequential transformation was probed by the isotope-labeled experiments. This strategy was further applied in the formal syntheses of indole alkaloids coerulescine and horsfiline. (Figure presented.).