NEW MATERIAL: A compound of formula VI [wherein R1 is H, an acyl, an alkylsilyl or tetrahydropyranyl; X is formula VII (wherein R2=R1) or formula VIII (wherein R3=R1; and R4 are each H or an alkyl), provided that when X is formula VII, and the stereochemical conformation at C-23 ad 25 are 25- hydroxyvitamin D3-26,23-lactone of a natural origin, R2 is an acyl, an alkylsilyl or the like in the case where R1 is H, and in the case where R2 is H, the situation is reverse to the above].
USE: A raw material for the synthesis of 25-hydroxyvitamin D3-26,23-lactone or the like.
PREPARATION: A compound of formula I (wherein R1 is H or a 1-5C alkyl) is reduced with a hydride to form an aldehyde of formula II, and this is subjected to the aldol condensation with e.g. acetone to form a compound of formula III. A side chain lactone is directly introduced into it by using a cyanide to form a compound of formula IV. This is photolyzed by irradiation with actinic radiations to form a compound of formula V. This compound is reacted at 50-80°C in a lower alcohol to obtain a compound of formula I (wherein X is formula VII).
| JPS53121736 | 22HYDROXYBUTYRATE DERIVATIVE |
| WO/2016/074699 | IMPROVMENTS IN OR RELATING TO ORGANIC COMPOUNDS |
| JPH06211737 | SUBSTITUTED CYCLOHEXANE DERIVATIVE FOR TREATING DISEASE |
HAINRITSUHI KEE SHIYUNOOZU
HAABAATO II PAREN
JIYOSEFU KEE UITSUKUMAN
MEARII EI FUIBITSUTSUANI
| JPH0130031B2 | 1989-06-15 | |||
| JPS46327Y1 | 1971-01-08 | |||
| JPS5584324U | 1980-06-10 |