6044-30-0Relevant academic research and scientific papers
Enantioselective cyclopropanation of conjugated cyanosulfones using carbohydrate-based crown ether catalysts
Nemcsok, Tamás,Rapi, Zsolt,Bagi, Péter,Guan, Ying Hou,Orbán, István,Keglevich, Gy?rgy,Bakó, Péter
, (2020/01/31)
A few new D-galactose- and D-glucose-based monoaza-15-crown-5 type lariat ethers have been synthesized. These macrocycles and their derivatives proved to be efficient catalysts in the cyclopropanation of (E)-3-phenyl-2-(phenylsulfonyl)acrylonitrile performed with diethyl bromomalonate under mild phase transfer conditions. Among the catalysts tested, the macrocycle having methyl α-D-galactopyranoside unit generated the highest asymmetric induction (80% ee). In the reactions of the aryl-substituted phenylsulfonyl-acrylonitrile derivatives, the cyclopropanation of the meta- and para-substituted starting materials took place with high ee values (75–84% ee). The cyclopropane derivatives synthesized from analogous α,β-unsaturated cyanosulfones containing naphthyl, pyridyl, furyl and thienyl groups were obtained with enantioselectivities up to 85%, and in excellent yields.
Enzymatic glucosylation of unnatural naphthols by a promiscuous glycosyltransferase from Aloe arborescens
Xie, Kebo,Zhang, Yujiao,Chen, Ridao,Chen, Dawei,Yang, Lin,Liu, Xia,Dai, Jungui
supporting information, p. 2118 - 2121 (2017/05/09)
Enzymatic glucosylation of unnatural products by natural glycosyltransferases (GTs) has great potential in creating novel and bioactive glucosides. A new GT (AaGT3) from Aloe arborescens exhibited catalytic promiscuity and high efficiency to diverse unnatural naphthols. By combing the substrate flexibility and catalytic reversibility of AaGT3, a cost-effective enzymatic approach to novel and bioactive unnatural glucosides was established. These studies indicate the significant potential of promiscuous natural GTs in synthesis of unnatural bioactive glucosides in drug discovery.
On the regioselectivity of the protease subtilisin towards the acylation of enantiomeric pairs of benzyl and naphthyl glycopyranosides. Part 2
Danieli, Bruno,Peri, Francesco,Roda, Gabriella,Carrea, Giacomo,Riva, Sergio
, p. 2045 - 2060 (2007/10/03)
Subtilisin-catalyzed esterification of several enatiomeric benzyl and naphthyl glycopyranosides has been investigated. The D-sugar derivatives were all good substrates and subtilisin regioselectivity was similar with all the compounds tested, the 3-OH being acylated predominantly. On the other hand, most of the L-glycopyranosides were transformed during longer reaction times with a lower regioselectivity, the 2-OH being preferentially but not exclusively acylated.
Non-amphiphilic carbohydrate liquid crystals containing an intact monosaccharide moiety
Smits,Engberts,Kelogg,Van Doren
, p. 185 - 199 (2007/10/02)
A chiral rigid moiety which forms the basis of a new class of non-amphiphilic carbohydrate liquid crystals has been developed. This moiety contains a fully intact glucopyranose ring embedded in a trans-decalin structure. The original carbohydrate is substituted so that only two hydroxyl groups are left, resulting in derivatives with reduced hydrophilicity. The substituents R and X-R′ on the 4,6-O-ylidene β-D-glucopyranoside are in the equatorial position and can be varied extensively, using straightforward synthetic procedures. Investigations as to the requirements for R and X-R′ for inducing liquid-crystalline behavior have shown that at least one of the substituents should contain a large, polarizable aromatic moiety. An aromatic Schiff base fulfils this requirement.
