63167-67-9Relevant academic research and scientific papers
Sequential directed epoxydation-acidolysis from glycals with MCPBA. A flexible approach to protected glycosyl donors
Marin, Irene,Castilla, Javier,Matheu, M. Isabel,Diaz, Yolanda,Castillon, Sergio
experimental part, p. 9622 - 9629 (2012/01/03)
4,6-Di-O-protected glucal and allal derivatives react with MCPBA to afford manno- and allo-1-O-m-chlorobenzoate derivatives, respectively, as a result of a syn epoxidation directed by the allylic hydroxyl group, and consecutive ring-opening by m-ClBzOH. When glucal and allal derivatives are fully protected, initial epoxidation proceeds mainly anti to the allylic group to give, after ring-opening, the corresponding pyranosyl chlorobenzoates. Stereoselectivity in the reaction of fully protected galactal derivatives was complete, although only a moderate increase in the syn epoxidation product was observed in 4,6- and 3,4-di-O-protected derivatives. 1-O-m-Chlorobenzoate 18 was selectively protected and activated as donor in the synthesis of disaccharide 21.
Stereocontrolled Total Synthesis of (-)-Maytansinol
Kitamura, Masato,Isobe, Minoru,Ichikawa, Yoshiyasu,Goto, Toshio
, p. 3252 - 3257 (2007/10/02)
Chiral maytansinol (1) was synthesized stereoselectively from D-mannose.Asymmetric centers of 1 were induced intramolecularly from an asymmetric carbon corresponding to C-7 via the common key intermediate 3 for maytansinoids.Key points are (i) the usage o
REGIOSELECTIVE MONOALKYLATION OF THE VICINAL cis-DIOL GROUP IN MANNOPYRANOSIDES USING DIARYLDIAZOALKANES-TIN(II) CHLORIDE
Petursson, Sigthor,wEbber, John M.
, p. 41 - 52 (2007/10/02)
Highly regioselective monoalkylations of the cis-2,3-diol group in mannopyranosides can be achieved with diaryldiazoalkanes in the presence of catalytic amounts of tin(II) chloride.With diazo(diphenyl)methane (1), its 4,4'-dimethyl (2) and 4,4'-dichloro (
SYNTHETIC STUDIES TOWARD MAYTANSINOIDS. PREPARATION OF THE OPTICALLY ACTIVE INTERMEDIATES FROM D-MANNOSE
Isobe, Minoru,Ichikawa, Yoshiyasu,Kitamura, Masato,Goto, Toshio
, p. 457 - 460 (2007/10/02)
Optically active intermediates (15 and 23) for maytansine were synthesized from D-mannose via heteroconjugate addition of methyllithium as a crucial step.
PRACTICAL SYNTHESIS OF O-β-D-MANNOPYRANOSYL-, O-α-D-MANNOPYRANOSYL-, AND O-β-D-GLUCOPYRANOSYL-(1->4)-O-α-L-RHAMNOPYRANOSYL-(1->3)-D-GALACTOSES
Betaneli, Vitali I.,Ovchinnikov, Michael V.,Backinowsky, Leon V.,Kochetkov, Nikolay K.
, p. 211 - 224 (2007/10/02)
The Koenigs-Knorr glycosylation of 4,6-O-ethylidene-1,2-O-isopropylidene-3-O-(2,3-O-isopropylidene-α-L-rhamnopyranosyl)-α-D-galactopyranose (3) by 4,6-di-O-acetyl-2,3-O-carbonyl-α-D-mannopyranosyl bromide (10), as well as Helferich glycosylations of 3 by tetra-O-acetyl-α-D-mannopyranosyl and -α-D-glucopyranosyl bromides, proceeded smoothly to give high yields of trisaccharide derivatives (12, 16, and 17).An efficient procedure for the transformation of 12, 16, and 17 into the α-deca-acetates of the respective trisaccharides has been developed.Zemplen deacetylation then afforded the title trisaccharides in yields of 53, 52, and 62percent respectively, from 3.A new route to 1,4,6-tri-O-acetyl-2,3-O-carbonyl-α-D-mannopyranose is suggested.
