1227732-55-9

Upstream product

• 1227732-54-8 (2R)-4-[(tert-butyl)(dimethyl)silyloxy]-1-{(2S,4S,6R,8S,10S)-10-[(tert-butyl)(dimethyl)silyloxy]-4-hydroxy-8-(2-hydroxyethyl)-1,7-dioxaspiro[5.5]undec-2-yl}but-2-yl 4-methoxybenzoate 
• 3282-30-2 pivaloyl chloride 

Downstream Products

• 1227732-56-0 (2R)-4-[(tert-butyl)(dimethyl)silyloxy]-1-{(2S,4S,6R,8S,10S)-10-[(tert-butyl)(dimethyl)silyloxy]-8-[2-(2,2-dimethylpropanoyloxy)ethyl]-4-methoxy-1,7-dioxaspiro[5.5]undec-2-yl}but-2-yl 4-methoxybenzoate 

Relevant academic research and scientific papers

Synthetic studies toward the CD spiroketal of spongistatins

Starting from the readily available meso-1,1' -methylenebis(8-oxabicyclo[3. 2.1]oct-6-en-3-one) (1), meso-1,1'-methylenebis[(4Ae,4'S,6fi,6'S)-4,6- dioxycyclohept-l-en-l-yl]tetrasilyl ethers 7 and 8 were obtained and transformed into all-syn 1,3,5,11,13,15-hexahydroxypentadeca-7,9-dione derivatives 9 and 10. The conversion of these intermediates into spiroketals was not successful. An alternative strategy based on the sequential and stereoselective functionalization of 1 afforded a 1-(2,4,6,8-tetrahydroxyoctyl)cyclohept-1-ene- 4,6-diol derivative [(+)-15, 94% ee], Ozonolysis of the cycloheptene moiety of (+)-19 provided the equatorial/axial spiroketal (+)21. Pivaloylation of its primary alcohol moiety and Meerwein methylation of the remaining secondary alcohol unit furnished (-)-24, a potential precursor of the ketal isomer of the CD fragment found in spongistatins 1 and 2.