342644-90-0

Upstream product

• 18162-48-6 tert-butyldimethylsilyl chloride 
• 377091-68-4 [3R-(1Z,3β,4α,5α)]-2-[3,4,5-trihydroxy-2-methylenecyclohexylidene]ethyl trimethylacetate 
• 3282-30-2 pivaloyl chloride 
• 244278-87-3 [3R-(1Z,3β,4α,5α)]-2-[5-(1,1-dimethylethyl)dimethylsilyloxy-3,4-isopropylidenedioxy-2-methylenecyclohexylidene]ethanol 
• 342644-83-1 [3R-(1Z,3β,4α,5α)]-2-[5-(1,1-dimethylethyl)dimethylsilyloxy-3,4-isopropylidenedioxy-2-methylenecyclohexylidene]ethyl trimethylacetate 
• 69-65-8 mannitol 
• 3969-59-3 mannitol triacetonide 
• 38145-93-6 1,2:3,4-di-O-isopropylidene-D-mannitol 
• 4239-90-1 (4S,4'R,5R)-2,2,2',2'-tetramethyl-5-vinyl-4,4'-bi(1,3-dioxolane) 
• 168109-89-5 (1R)-1-((4R,5R)-2,2-dimethyl-5-vinyl[1,3]dioxolan-4-yl)ethane-1,2-diol 

Downstream Products

• 342644-91-1 [3R-(1Z,3β,4α,5α)]-2-[3,5-bis[(1,1-dimethylethyl)dimethylsilyloxy]-4-(3-hydroxypropoxy)-2-methylenecyclohexylidene]ethanol 
• 342645-07-2 (1α,2β,3β,5Z,7E,20S)-1,3-bis[(1,1-dimethylethyl)dimethyl-silyloxy]-2-[3-[(1,1-dimethylethyl)dimethylsilyloxy]propoxy]-9,10-secopregna-5,7,10(19)-triene-20-methyl 4-methylbenzenesulfonate 
• 342645-84-5 (1β,2α,3α,5Z,7E)-1,3-bis[(1,1-dimethylethyl)dimethylsilyloxy]-2-[3-[(1,1-dimethylethyl)dimethylsilyloxy]propoxy]-25-trimethylsilyloxy-9,10-secocholesta-5,7,10(19)-triene 
• 104121-92-8 Eldecalcitol 
• 200636-50-6 [3R-(1Z,3β,4α,5α)]-2-[3,5-bis[(1,1-dimethylethyl)dimethylsilyloxy]-4-[3-[(1,1-dimethylethyl)dimethylsilyloxy]propoxy]-2-methylenecyclohexylidene]-1-chloroethane 
• 200636-54-0 [3R-(1Z,3β,4α,5α)]-[2-[3,5-bis[(1,1-dimethylethyl)dimethylsilyloxy]-4-[3-[(1,1-dimethylethyl)dimethylsilyloxy]propoxy]-2-methylenecyclohexylidene]ethyl]diphenylphosphine oxide 
• 342645-82-3 [3R-(1Z,3β,4α,5α)]-2-[3,5-bis[(1,1-dimethylethyl)dimethylsilyloxy]-4-(3-hydroxypropoxy)-2-methylenecyclohexylidene]-1-chloroethane 

Relevant academic research and scientific papers

Structural revisions of the reported A-ring phosphine oxide synthon for ED-71 (Eldecalcitol) and a new synthesis

In a reported procedure for the synthesis of the ED-71 A-ring phosphine oxide, we discovered that unusual TBS transfer occurred from the 1α-position to the sterically more constrained 2β-position, and the subsequent Michael addition of ethyl acrylate predominated at the 1α-position. The X-ray analysis of a key intermediate confirmed our observations. We made a structural revision of the reported A-ring phosphine oxide synthon and ED-71. In addition, we provided the first stereoselective synthetic approach to ED-71 A-ring phosphine oxide applying the stereochemistry of d-mannitol.

Parallel synthesis of a vitamin D3 library in the solid-phase

A highly efficient synthesis of the vitamin D3 system on solid support is described. Two synthetic strategies for the solid-phase synthesis of vitamin D3 were developed. One is for 11-hydroxy analogues, and the other is for most other synthetic analogues. In the latter strategy, the sulfonate-linked CD-ring 58 was initially immobilized on PS-DES resin to give solid-supported CD-ring 63 (Scheme 10). Similarly, solid-supported CD-ring 63 was prepared by attachment of the CD-ring 10 to the chlorosulfonate resin 64. The vitamin D3 system was synthesized by Horner-Wadsworth-Emmons reaction of the A-ring phosphine oxide to a solid-supported CD-ring, followed by simultaneous introduction of the side chain and cleavage from resin with a Cu1-catalyzed Grignard reagent. Parallel synthesis of the vitamin D3 analogues was accomplished by a split and pool methodology utilizing radio frequency encoded combinatorial chemistry, and a manual parallel synthesizer for side chain diversification and deprotection. Additionally, we demonstrated the synthesis of various A-rings in a similar protocol for efficient preparation of building blocks.