29745-09-3Relevant academic research and scientific papers
Pd-Catalyzed Remote Site-Selective and Stereoselective C(Alkenyl)-H Alkenylation of Unactivated Cycloalkenes
Mao, Chun-Li,Zhao, Sheng,Zang, Zhong-Lin,Xiao, Lin,Zhou, Cheng-He,He, Yun,Cai, Gui-Xin
, p. 774 - 787 (2020/01/09)
A palladium-catalyzed alkenylation involving remote δ-position C(alkenyl)-H activation of cycloalkenes reacting with electron-deficient alkenes is described. This method features excellent site selectivity and stereoselectivity to efficiently afford only E-selective highly substituted 1,3-diene derivatives with extra-ligand-free and good functional group tolerance including estrone and free N-H tryptamine under weakly alkaline conditions. Mechanistic studies suggest that picolinamide as a bidentate directing group enables the formation of unique alkenyl palladacycle intermediates.
Searching for new agents active against Candida albicans biofilm: A series of indole derivatives, design, synthesis and biological evaluation
Pandolfi, Fabiana,D'Acierno, Federica,Bortolami, Martina,De Vita, Daniela,Gallo, Fabio,De Meo, Alessandra,Di Santo, Roberto,Costi, Roberta,Simonetti, Giovanna,Scipione, Luigi
, p. 93 - 106 (2019/01/23)
Candida albicans biofilm represents a major clinical problem due to its intrinsic tolerance to anti-fungal compounds and it has been highly related to infections in catheterized patients. Few compounds are described as able to inhibit biofilm formation or to interfere with preformed biofilm of C. albicans. Here we report the in vitro evaluation of anti-biofilm activity on C. albicans ATCC 10231 of a series of new and already known amine and amide indole derivatives. Among the studied compounds, fifteen resulted active on C. albicans ATCC 10231 biofilm, with BMIC50 ≤ 16 μg/mL. Three of them (7, 23 and 33) showed a selectivity towards mature biofilm and the most active of them was the compound 23 (BMIC50 = 4 μg/mL). On the other hands, two different compounds (21 and 22) were selective towards biofilm formation with BMIC50 values of 8 μg/mL. Otherwise, compounds 16 and 17 resulted active on biofilm formation, with BMIC50 of 8 μg/mL and 2 μg/mL respectively, and on mature biofilm with BMIC50 of 2 μg/mL. These two last compounds also showed an interesting activity towards the planktonic cells of C. albicans. A selection of the more active compounds was also evaluated on different C. albicans strains (PMC1042, PMC1083 and ATCC 10261), showing a comparable or higher anti-biofilm activity, especially on mature biofilm. In vivo toxicity studies using the Galleria mellonella larvae, were finally carried out on more active indole derivatives, showing that they are poorly toxic even at the highest concentrations tested (500–1000 μg/mL).
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.
