Showing papers on "Ferrier rearrangement published in 2007"
TL;DR: Er(OTf)(3) is a useful catalyst for the Ferrier rearrangement furnishing high yields of O- and S-glycosides and the catalyst, which is also commercially available, can be recovered and reused.
44 citations
TL;DR: RCAI-56 (3), a carbocyclic analogue of KRN7000 (1) was synthesized through an efficient coupling of a carba-α-d-galactose derivative 11 with cyclic sulfamidate derivative 13 of phytosphingosine to give 15.
43 citations
TL;DR: Two new glycosylsulfamides were tested as carbonic anhydrase (CA II) inhibitors and showed good properties in the micromolar range.
40 citations
TL;DR: In this article, the first total synthesis of an enantiomeric pure ara-type cyclohexenyl nucleoside was described, which was based on a methyl-α-d -glucopyranose and involves an isomerization step, selective protection/deprotection chemistry, a Ferrier rearrangement and a Mitsunobu reaction.
40 citations
TL;DR: In this paper, a Ferrier rearrangement reaction and BF3·OEt2-induced peroxidation was employed to construct key intermediates 2,3-unsaturated glycosides and α,β-unaturated lactones from peracetyl rhamnal.
29 citations
TL;DR: Three compounds reacted with N-hydroxymethylphthalimide and boron trifluoride etherate to produce the corresponding phthalimidomethyl unsaturated glycosides via Ferrier rearrangement were found to possess potent activity compared to hydrocortisone sodium succinate (HSS).
28 citations
TL;DR: Stereoselective synthesis of trans-2,6-disubstituted-3,4-dihydropyrans has been achieved from a simple homoallylic alkoxyether via a three-step sequence: electrophile-induced ether transfer, cyclization, and functionalization, which is highlighted by a rare example of Ferrier rearrangement of allylic ether.
Abstract: Stereoselective synthesis of trans-2,6-disubstituted-3,4-dihydropyrans has been achieved from a simple homoallylic alkoxyether via a three-step sequence: electrophile-induced ether transfer, cyclization, and functionalization, which is highlighted by a rare example of Ferrier rearrangement of allylic ether. This methodology was successfully implemented for the asymmetric synthesis of a C7−C17 fragment of swinholide A.
27 citations
TL;DR: The first regioselective synthesis of β-galactofuranosides by Fischer glycosidation of GalNAc with methanol catalyzed by HY, HZSM-5 and HBEA acid zeolites was reported in this article.
Abstract: We report herein the first regioselective synthesis of β-galactofuranosides by Fischer glycosidation of GalNAc with methanol catalyzed by HY, HZSM-5 and HBEA acid zeolites. The zeolite HY (Si/Al ratio 3.1) was the most efficient catalyst, leading to the highest yield of methyl β-galactofuranoside, isolated as its acetylated or isopropylidene derivatives, indicating that with large pore zeolites, the reaction efficiency depends upon the concentration of the zeolite acid sites and its hydrophilicity. However, the best regioselectivity for β-galactofuranoside versus β-galactopyranoside was obtained with the medium pore zeolite HZSM-5, which also led to the lowest starting material conversion, suggesting that both the zeolite pore size and topology are determinant for the obtained results. Furthermore, these acid zeolites proved to be efficient catalysts to transform 1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy- d -arabino-hex-1-enitol (6) (3,4,6-tri-O-benzyl- d -glucal) exclusively in the 2,3-unsaturated-O- and -S-α- d -glycosides by Ferrier rearrangement, in moderate yield. For this reaction, the number of acid sites was the key factor for the reaction yield, being HY (Si/Al ratio 3.1) also the most effective zeolite.
21 citations
TL;DR: Fe2(SO4)3···xH2O catalyzes the Ferrier reaction of per−O−acetylated/benzylated glycals with alcohols to give 2,3−unsaturated α−glycosides in a few minutes under microwave irradiation as mentioned in this paper.
17 citations
TL;DR: Amberlyst 15 serves as an inexpensive, effective, and environmentally friendly catalyst in converting 3,4,6,tri-O-acetyl-D-glucal into 2,3,unsaturated O and S-glycosides via Ferrier rearrangement in moderate to excellent yields with high α selectivity as discussed by the authors.
11 citations
TL;DR: Although it is notoriously difficult to chemically protect the primary OH groups in beta-lactoside derivatives, a 6,6'-disilylated intermediate was prepared in 82% yield and the desired trisaccharide was isolated in 53%ield and easily deprotected in four steps.
Abstract: In our efforts to design new anti-cancer vaccines based on the tumor associated carbohydrate antigen dimeric Lex, we have synthesized the fragment GlcNAc-beta-(1-->3)-Gal-beta-(1-->4)-GlcNAc-beta-(1-->O)-Me Although it is notoriously difficult to chemically protect the primary OH groups in beta-lactoside derivatives, a 6,6'-disilylated intermediate was prepared in 82% yield It was converted to a glycosyl acceptor free at O-3' that was glycosylated with a 2-deoxy-2-phthalimido trichloroacetimidate glucosyl donor This glycosylation required large amounts of TMSOTf to proceed Such conditions led to the formation of a Ferrier rearrangement glycosylation product Despite these hurdles, the desired trisaccharide was isolated in 53% yield and easily deprotected in four steps
TL;DR: Amino acid 2,3-unsaturated glycopyranosyls have been prepared by the Ferrier rearrangement of acetyl protected glucals and PEG-bound amino acids in the presence of a catalytic quantity of BF3·Et2O in CH2Cl2 at ambient temperature.
TL;DR: The synthesis of a novel carbasugar amino acid (15), starting from D‐glucose and using the Ferrier rearrangement as a key step, is reported.
TL;DR: A simple optical resolution of dibenzo[a,g]fluorenol has been accomplished via borontrifluoride•mediated Ferrier rearrangement reaction as discussed by the authors.
TL;DR: Amberlyst 15 serves as an inexpensive, effective, and environmentally friendly catalyst in converting 3,4,6,tri-O-acetyl-D-glucal into 2,3,unsaturated O and S-glycosides via Ferrier rearrangement in moderate to excellent yields with high α selectivity as mentioned in this paper.
Abstract: Amberlyst 15 serves as an inexpensive, effective, and environmentally friendly catalyst in converting 3,4,6‐tri‐O‐acetyl‐D‐glucal (1) into 2,3‐unsaturated O‐ and S‐glycosides via Ferrier rearrangement in moderate to excellent yields with high α selectivity.