Glycosylation Reaction of <i>Thioglycosides</i> by Using Hypervalent Iodine(III) Reagent as an Excellent Promoter
作者:Tetsuya Kajimoto、Koji Morimoto、Ryosuke Ogawa、Toshifumi Dohi、Yasuyuki Kita
DOI:10.1248/cpb.c16-00203
日期:——
Thioglycosides are available donors in glycosylation due to the stability of the anomeric C-S bond under general reaction conditions of protection and deprotection, and offer orthogonality in their activation. We report now that the hypervalent iodine effectively induced glycosylationreaction of thioglycosides with various alcohols. This method features a high efficiency, completion in a short time
Phenyliodine Bis(trifluoroacetate) (PIFA) as an Excellent Promoter of 2-Deoxy-2-phthalimido-1-thioglycosides in the Presence of Triflic Acid in Glycosylation Reactions
作者:Tetsuya Kajimoto、Koji Morimoto、Ryosuke Ogawa、Toshifumi Dohi、Yasuyuki Kita
DOI:10.1002/ejoc.201500186
日期:2015.4
A combination of phenyliodinebis(trifluoroacetate) (PIFA) and trifluoromethanesulfonic acid was found to be an effective activator for the glycosylationreaction, of which the glycosyl donor was p-(octyloxy)phenyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-1-thio-D-glucopyranoside or p-(octyloxy)phenyl 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-1-thio-D-galactopyranoside. The reaction proceeded with good
group of the C-6 position of derivatives of D-glucosyl sulfoxide. Successive reduction of the resulting disaccharyl sulfoxides provided the corresponding thioglycosides, which could be used as the glycosyl donors in another glycosylation reaction to afford trisaccharides in good yield. The present method would be useful for the block synthesis of glycosyl donors in the total synthesis of blanched oligosaccharides
Metal Thietane Compound, Polymerizable Composition Containing the Compound, Resin and Use of the Resin
申请人:Murakami Masakazu
公开号:US20130018169A1
公开(公告)日:2013-01-17
Polymerizable compositions containing at least one metal thietane compound represented by general formulas (110), (201) or (120), respectively, wherein said formulas are as follows:
and wherein the identified moieties and n, p, q and r are defined.
METAL THIETANE COMPOUND, POLYMERIZABLE COMPOSITION CONTAINING THE COMPOUND, RESIN AND USE OF THE RESIN
申请人:Murakami Masakazu
公开号:US20100240862A1
公开(公告)日:2010-09-23
Disclosed is a metal thietane compound represented by the following general formula (120),
(wherein, in the above general formula (120), M is a member selected from the group consisting of Bi, Sb, Ti, Zr and Ta; X
1
and X
2
are each independently a sulfur atom or an oxygen atom; R
1
is a divalent organic group; the bond between M and T shown by a dotted line and a solid line represents a single or double bond; m is an integer of 0 or 1 or more; n is the number of valence of M; and p is an integer of equal to or more than 1 and equal to or less than n, provided that when r is 1, q is 0 and Y is a monovalent inorganic or organic group; when r is 1 and n-p-q is 2 or more, a plurality of Ys contained are each independently selected from monovalent inorganic or organic groups; when r is 1 and n-p-q is 2 or more, a plurality of Ys may be bonded to each other to form a ring containing M; when r is 2, n-p-q is 1 or 2 and Y is a divalent group; when r is 2 and n-p-q is 2, two Ys may form a ring together with two Ms; and when r is 2 and q is 2, a plurality of Ts contained are each independently selected from inorganic or organic groups).