1492-30-4Relevant articles and documents
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Murakami,Y. et al.
, p. 24 - 32 (1977)
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Enzyme mediated-transesterification of verbascoside and evaluation of antifungal activity of synthesised compounds
Khazir, Jabeena,Ali, Intizar,Khan, Inshad Ali,Sampath Kumar, Halmuthur Mahabalarao
, p. 727 - 734 (2015/09/23)
Enzymatic acylation of verbascoside, a polyhydroxylated natural product, has been reported in this study using five different commercial lipases and taking p-nitrophenyl alkanoates as acyl donors. Out of these enzymes, the immobilised Candida antarctica lipase B was found as the enzyme of choice. Mono-and di-acylated products were formed, with mono as major product indicating high regioselective nature of such transformations. A series of acyl esters of verbascoside have been synthesised by this enzymatic transesterification methodology. The lipophilicity of the synthesised analogues was also checked. The analogues were further subjected to synergistic antifungal activity with amphotericin B (AmB) against Candida albicans. Fourfold reduction in minimum inhibitory concentration of AmB was observed with few synthesised analogues such as verbascoside 4″-octanoate (3b), verbascoside 4″-palmitate (3d) and verbascoside 4″,4′-dipalmitate (4d) at a concentration of 0.5 g/mL.
Synthesis of Ceramide Analogues Having the C(4)-C(5) Bond of the Long-Chain Base as Part of an Aromatic or Heteroaromatic System
Chun, Jiong,He, Linli,Byun, Hoe-Sup,Bittman, Robert
, p. 7634 - 7640 (2007/10/03)
Two efficient and stereoselective methods are described for the preparation of aryl and heteroaryl ceramide analogues 2 and 3. The first route involves the addition of an aryllithium or a heteroaryllithium reagent (7a or 25a, respectively) to the L-serine-derived aldehyde 4, followed by hydrolysis of the oxazolidine, liberation of the amino group, and N-acylation. The second route, which was used to prepare arylceramide analogue 2 in eight steps and 28% overall yield starting with 3-bromobenzaldehyde, utilizes a Heck reaction to afford (E)-α,β-unsaturated ester 16, then osmium-catalyzed asymmetric dihydroxylation for the introduction of the desired chirality at C-2 and C-3. Regioselective α-azidation of α-O-nosyl-β-hydroxyester 18 with sodium azide, followed by LiAlH4 reduction of the azido and ester groups and N-acylation, complete the synthesis of arylceramide analogue 2.
