23009-68-9

Upstream product

• 186581-53-3 diazomethane 
• 34698-05-0 methyl 2-O-methyl-β-D-galactopyranoside 
• 20908-66-1 methyl 2-O-methyl-α-D-glucopyranoside 
• 67-56-1 methanol 
• 91297-94-8 3-O-β-D-glucopyranosyl-(1->2)-<β-D-xylopyranosyl-(1->3)>-β-D-glucopyranosyl-(1->4)-β-D-galactopyranosyl-(25 R,S)-spirost-5-en-3β,14α-diol dodecamethyl ether 

Relevant academic research and scientific papers

Regioselective methylation of methyl glycopyranosides with diazomethane in the presence of transition-metal chlorides and of boric acid

Partial methylation of the methyl pyranosides of a number of pentoses, hexoses, 6-deoxyhexoses, methyl uronates and their methyl ethers with diazomethane in the presence of transition-metal chlorides and boric acid was studied. It was found for methyl glycosides of pentoses and 6-deoxyhexoses that tin(II), antimony(III), and titanium(IV) chlorides as well as boric acid promoted substitution mainly of OH-3, but with cerium(III) and zinc(II) salts mainly substitution of OH-2 was observed. Methylation of methyl β-l-rhamnopyranoside demonstrated higher reactivity of OH-2 in all cases. The methylation of methyl glycosides of hexoses in the presence of tin(II), antimony(III) and cerium(III) chlorides gave mainly 3-methyl ethers. The 3-methyl ethers, which are not involved in further complexation, accumulated up to 50-80% of the reaction mixture (95-100% of monomethyl ether fraction). Convenient preparative syntheses of methyl ethers for a number of sugars are suggested. Copyright (C) 1999 Elsevier Science Ltd.

THE STEROIDAL GLYCOSIDES OF THE FLOWERS OF YUCCA GLORIOSA

Four steroidal compounds were isolated from the fresh flowers of Yucca gloriosa and their structures were elucidated as tigogenin 3-O-β-D-xylopyranosyl-β-lycotetraoside, gitogenin 3-O-β-D-xylopyranosyl-β-lycotetraoside, gitogenin 3-O-α-rhamnopyranosyl-β-lycotetroside and proto-type of gitogenin 3-O-β-D-xylopyranosyl-β-lycotetraoside, on the basis of physical and chemical investigation.Key Word Index - Yucca gloriosa; Liliaceae; tigogenin glycoside; gitogenin glycosides; furostanol glycoside.

Five Steroidal Components from the Rhizomes of Polygonatum odoratum var. pluriflorum

Five steroidal components (PO-a(1)-PO-e(5)) were obtained from the methanolic extract or its partial hydrolysate of the fresh rhizomes of Polygonatum odoratum var.Pluriflorum, and their chemical structures were characterized as (25 R and S)-spirost-5-en-3β,14α-diol, 3-O-β-D-glucopyranosyl-(1->2)-3)>-β-D-glucopyranosyl-(1->4)-β-D-galactopyranosyl(=β-lycotetraosyl)-(25 R and S)-spirost-5-en-3β,14α-diol, 3-O-β-lycotetraosyl-22-methoxy-(25 R and S)-furost-5-en-3β,14α,26-triol 26-O-β-D-glucopyranoside, 3-O-β-D-glucopyranosyl-(1->2)-3)>-β-D-glucopyranosyl(1->4)-β-D-galactopyranosyl-22-methoxy-(25 R and S)-furost-5-en-3β,14α,26-triol 26-O-β-D-glucopyranoside and 3-O-β-lycotetraosyl yamogenin, respectively.Moreover, (25 S)-spirost-5-en-3β,14α-diol (7) was isolated from a mixture of the (25 R) and (S) derivatives of PO-a (1) and it was designated as neoprazerigenin A.Keywords - Polygonatum odoratum var. pluriflorum; Liliaceae; neoprazerigenin A; spirostanol glycoside; furostanol glycoside.

Steroidal glycosides of Tribulus terrestris Linn.

Besides β-sitosterol-β-D-glucoside and dioscin, two new steroidal glycosides, neohecogenin glucoside and tribulosin, isolated from the aerial part of Tribulus terrestris Linn. were respectively shown to be neohecogenin-3-O-β-D-glucopyranoside (2) and neotigogenin-3-O-β-D-xylopyranosyl(1->2)-3)>-β-D-glucopyranosyl(1->4)-2)>-β-D-galactopyranoside (7).