35068-75-8

Upstream product

• 143-62-4 (+)-digitoxigenin 
• 572-09-8 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide 
• 108-24-7 acetic anhydride 
• 17059-16-4 digitoxigenin 3-O-β-D-glucoside 
• 572-09-8 2,3,4,6-tetra-O-acetyl-D-glucopyranosyl bromide 
• 83-87-4 D-glucose pentaacetate 
• 466-09-1 uzarigenine 
• 6877-82-3 Desglucouzarin 

Relevant academic research and scientific papers

Synthesis of cardenolide glycosides and putative biosynthetic precursors of cardenolide glycosides

A rapid and efficient procedure for glycosylation of steroids was established using a modified Koenigs-Knorr procedure. Peracetylated β- glycosides were synthesized by reaction of cardenolides, various pregnanes and 23-nor-5,20(22)E-choldienic acid at room temperature with the peracetylated 1-bromo derivatives of D-glucose, D-galactose, D-fucose and cellobiose. Subsequent deprotection was performed by alkaline hydrolysis with sodium methoxide. Structures of the respective glycosides were established by NMR techniques. The complete protocol was shown to be non-destructive at all stages to the sugar moiety and the steroidal nucleus. The γ-unsaturated lactone ring of the cardenolides was shown to remain intact and no formation of C-14 unsaturated compounds was observed.

BIOTRANSFORMATION OF DIGITOXIGENIN BY CELL SUSPENSION CULTURES OF STROPHANTHUS INTERMEDIUS

Biotransformation products of digitoxigenin by cell suspension cultures of Strophanthus intermedius were isolated and their structures elucidated as 3-epidigitoxigenin, 3-epi-17βH-digitoxigenin, gitoxigenin, periplogenin, 3-epigitoxigenin, 3-epiperiplogenin and digitoxigenin β-D-glucoside, respectively.Furthermore, 3-epi-17βH-periplogenin, 3-epidigitoxigenin β-D-glucoside and digitoxigenone were identified by TLC and HPLC.Biotransformation reactions of the digitoxigenin molecule by plant cell cultures are summarized and discussed comparatively. - Keywords: Strophanthus intermedius; Apocynaceae; cell cultures; biotransformation; 5β- and 16β-hydroxylation; cardenolides; digitoxigenin; 3-epigitoxigenin.

Cardiac glycosides: 2. Synthesis of glucose and galactose analogs.

Five cardioactive steroid genins 1a to 5a of widely varying C17 beta-side groups were converted by modified Koenigs-Knorr reactions into the corresponding beta-D-glucosides 1c to 5c and beta-D-galactosides 1e to 5e. The genins included digitoxigenin (3 beta, 14-dihydroxy-5 beta, 14 beta-card-20-(22)-enolide, 1a); (20R)-20, 22-dihydrodigitoxigenin (3 beta, 14-dihydroxy-5 beta, 14 beta, 20R-cardanolde, 2a); 3 beta, 14-dihydroxy-22-methylene-5 beta, 14 beta, 20S-cardanolide (3a); methyl 3 beta, 14-dihydroxy-5 beta, 14 beta-pregn-20(E)-ene-21-carboxylate (4a); and methyl 3 beta, 14-dihydroxy-21-methylene-5 beta, 14 beta-pregnane-21-carboxylate (5a).

Cardenolide analogues. 11. Improved method for the use of Fetizon's reagent in the synthesis of cardiac glycosides

An improved procedure has been developed for preparing glycosides of cardenolide genins. The method uses specially prepared Fetizon's reagent as catalyst, combined, in most cases, with mercuric cyanide and mercuric bromide. In the presence of this catalyst, genins react readily, at room temperature, with per-acetylated 1-bromo-sugars to give the acetylated glycosides in high yield with little or no side reaction. The reaction proceeds almost to completion in 30 to 60 min. The free glycoside is obtained by mild deacetylation using triethylamine/methanol/water (20:20:1) at room temperature for 72 h. Proof of structure was obtained using chemical ionization mass spectrometry, NMR spectroscopy and comparison of physical constants with published data. The compounds were tested for inotropic activity using the isolated guinea pig atrium.

BIOTRANSFORMATION OF DIGITOXIGENIN BY CELL SUSPENSION CULTURES OF DIGITALIS PURPUREA

Digitoxigenin was oxidized to digitoxigenone which was reduced to epidigitoxigenin and then glucosylated to epidigitoxigenin glucoside by cell cultures of Digitalis purpurea.The epidigitoxigenin glucoside, together with digitoxigenone and epidigitoxigenin, was isolated in considerable amounts, whereas digitoxigenin glucoside could only be detected in low concentration.Furthermore, it was confirmed by TLC and HPLC that digitoxigenin was hydroxylated to periplogenin.Key Word Index-Digitalis purpurea; Scrophulariaceae; tissue cultures; biotransformation; hydroxylation; glucosylation; steroid; digitoxigenin; digitoxigenone; epidigitoxigenin; periplogenin; digitoxigenin glucoside; epidigitoxigenin glucoside.