488-38-0Relevant academic research and scientific papers
Organocatalytic Synthesis of Higher-Carbon Sugars: Efficient Protocol for the Synthesis of Natural Sedoheptulose and d-Glycero-l-galacto-oct-2-ulose
Popik, Oskar,Pasternak-Suder, Monika,Ba?, Sebastian,Mlynarski, Jacek
, p. 717 - 721 (2016/08/27)
Herein we report a short and efficient protocol for the synthesis of naturally occurring higher-carbon sugars—sedoheptulose (d-altro-hept-2-ulose) and d-glycero-l-galacto-oct-2-ulose—from readily available sugar aldehydes and dihydroxyacetone (DHA). The key step includes a diastereoselective organocatalytic syn-selective aldol reaction of DHA with d-erythrose and d-xylose, respectively. The methodology presented can be expanded to the synthesis of various higher sugars by means of syn-selective carbon–carbon-bond-forming aldol reactions promoted by primary-based organocatalysts. For example, this methodology provided useful access to d-glycero-d-galacto-oct-2-ulose and 1-deoxy-d-glycero-d-galacto-oct-2-ulose from d-arabinose in high yield (85 and 74 %, respectively) and high stereoselectivity (99:1).
Role of the side chain stereochemistry in the α-glucosidase inhibitory activity of kotalanol, a potent natural α-glucosidase inhibitor. Part 2
Tanabe, Genzoh,Matsuoka, Kanjyun,Yoshinaga, Masahiro,Tsutsui, Nozomi,A. Amer, Mumen F.,Nakamura, Shinya,Nakanishi, Isao,Muraoka, Osamu,Xie, Weijia,Wu, Xiaoming,Yoshikawa, Masayuki
, p. 6321 - 6334,14 (2012/12/12)
To examine the role of the side chain of kotalanol (2), a potent natural α-glucosidase inhibitor isolated from Salacia reticulata, on inhibitory activity, four diastereomers (11a-11d) with reversed configuration (S) at the C-4′ position in the side chain were synthesized and evaluated. Two of the four (11b and 11d) significantly lost their inhibitory activity against both maltase and sucrase, while the other two (11a and 11c) sustained the inhibitory activity to a considerable extent, showing distinct activity in response to the change of stereochemistry of the hydroxyls at the 5′and 6′ positions. Different activities were rationalized with reference to in silico docking studies on these inhibitors with hNtMGAM. Against isomaltase, all four analogs showed potent inhibitory activity as well as 2, and 11b and 11d exhibited enzyme selectivity.
Four orders of magnitude rate increase in artificial enzyme-catalyzed aryl glycoside hydrolysis
Ortega-Caballero, Fernando,Bjerre, Jeannette,Laustsen, Line Skall,Bols, Mikael
, p. 7217 - 7226 (2007/10/03)
(6A6DR)-6A,6D-Di-C-cyano- β-cyclodextrin (1) and 6A,6D-di-C-cyano-α- cyclodextrin (2) were synthesized and shown to catalyze hydrolysis of aryl glycosides into glucose and phenol with a reaction following Michaelis-Menten kinetics. At pH 8.0 and 59 °C hydrolysis of 4-nitrophenyl α-glucopyranoside was catalyzed by 1 with KM = 10.5 ± 1.5 mM, kcat = 1.42(±0.09) × 10-4 s -1 and kcatk/uncat = 7922, Catalysis was observed with a concentration of 1 as low as 10 μM. Hydrolysis of the other aryl glycosides containing stereochemical variation in the sugar-moiety and 4-nitro-, 2-nitro-, 2-aldehydo-, and 2,4-dinitro- were also catalyzed by 1 and 2 with kcat/kuncat ranging from 4 to 7100. Hydrolysis of a phenyl β-D-glucoside or the thioglycoside tolylthio β-D-glucoside was also catalyzed. From a series of prepared analogues of 1 it was found that the catalysis was associated with the hydroxyl groups α to the nitril groups. The monocyanohydrin 6-C-cyano-β-cyclodextrin (3) was also found to catalyze the hydrolysis of 4-nitrophenyl β-glucopyranoside with k Cat/kuncat = 1356. It was proposed that the cyclodextrin cyanohydrins 1-3 catalyze the hydrolysis by general acid catalysis on the bound substrate.
Ascent of the Aldose Series by Four Carbon Atoms: Total Synthesis of D-glycero-D-talo-L-talo-Undecose Pentaacetonide
Casiraghi, Giovanni,Colombo, Lino,Rassu, Gloria,Spanu, Pietro
, p. 2135 - 2139 (2007/10/02)
Enantiomerically pure undecose acetonide 9 was synthesized, through heptose intermediate 5, starting with D-glyceraldehyde acetonide (1).The key steps were two consecutive four-carbon homologations, each consisting of four reactions: (i) stereoselective elongation of the aldehyde precursor with 2-(trimethylsiloxy)furan, giving Cn+4 butenolide templates 2 and 6, (ii) anti-selective cis-dihydroxylation of the butenolide double bond, giving fully functionalized lactones 3 and 7, (iii) lactone ring opening and protection, giving open-chain methyl esters 4 and 8, and (iv) DIBAL reduction to aldoses 5 and 9.At the end of the eight-step sequence, undecose 9 was prepared in a 5.1percent overall yield, which corresponded to a 69.5percent average yield per step.
THE SYNTHESIS OF SOME SEVEN-CARBON SUGARS via THE OSMYLATION OF OLEFINIC SUGARS
Brimacombe, John S.,Kabir, Abul K. M. S.
, p. 35 - 52 (2007/10/02)
The stereochemical outcome of the catalytic osmylation of 6,7-dideoxy-1,2:3,4-di-O-isopropylidene-α-D-galacto-hept-6-enopyranose (10), 5,6-dideoxy-1,2-O-isopropylidene-α-D-xylo-hex-5-enofuranose, (E)- and (Z)-3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-α-D-xylo-hept-5-enofuranose (20 and 27, respectively), methyl (Z)-3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-α-D-xylo-hept-5-enofuranuronate (26), (E)-3-O-benzyl-5,6-dideoxy-1,2-O-isopropylidene-α-D-ribo-hept-5-enofuranose, benzyl (E)- and (Z)-5,6-dideoxy-2,3-O-isopropylidene-α-D-lyxo-hept-5-enofuranoside (46 and 50, respectively), and methyluronate (49) has been examined.Such oxidations led to satisfactory syntheses of L-glycero-D-gluco-heptose and the corresponding heptitol (from 20), L-glycero-D-gulo-heptitol (from 26), D-glycero-D-gluco-heptitol (from 27), D-glycero-D-galacto-heptitol (from 10 and 46), (meso)-glycero-gulo-heptitol (from 49), and D-glycero-D-manno-heptitol (from 50).
