124780-53-6

Upstream product

• 867-13-0 diethoxyphosphoryl-acetic acid ethyl ester 
• 124780-62-7 methyl 2-O-benzyl-3,4-O-isopropylidene-α-D-galactodialdo-1,5-pyranoside 
• 27851-16-7 methyl 2-O-benzyl-3,4-O-isopropylidene-α-D-galactopyranoside 
• 3396-99-4 methyl α-D-galactopyranoside 
• 100-39-0 benzyl bromide 
• 124780-61-6 ((3aS,4R,6S,7R,7aS)-7-Benzyloxy-6-methoxy-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyran-4-ylmethoxy)-tert-butyl-diphenyl-silane 
• 131089-35-5 (3aR,4S,6R,7S,7aS)-6-(tert-Butyl-diphenyl-silanyloxymethyl)-4-methoxy-2,2-dimethyl-tetrahydro-[1,3]dioxolo[4,5-c]pyran-7-ol 
• 114217-35-5 methyl 6-O-(tert-butyldiphenylsilyl)-α-D-galactopyranoside 

Downstream Products

• 124780-66-1 methyl (E)-2,3-di-O-benzyl-6,7,8-trideoxy-α-D-galacto-oct-6-enopyranoside 

Relevant academic research and scientific papers

Stereocontrolled lincomycin synthesis

The synthesis from methyl α-D-galactopyranoside (6) of methyl thiolincosaminide (2), the direct synthetic precursor to lincomycin (1), is presented. The key step for controlling the off-pyranose stereocenters C-6 and C-7 is a novel intramolecular nitrogen delivery reaction using epoxy alcohol 10. Reaction of 10 with dimethylcyanamide in the presence of sodium hydride and imidazole leads to the oxazoline 14, a protected vicinal amino alcohol. The synthesis is completed by efficient exchange of acetal for thioacetal, followed by hydrolysis of the oxazoline and removal of the benzyl groups. The target 2 is obtained in 22 steps and 28% overall yield from 6.