| 摘要 |
<p>1433973 Cyclopenta[b]furan derivatives UPJOHN CO 11 July 1974 [28 June 1973] 42612/75 Divided out of 1433971 Heading C2C Novel optically active cyclopenta[b]furan derivatives of the formula or racemates thereof, wherein R 1 is H, C 1-19 alkyl or C 7-12 aralkyl optionally substituted in the ring with up to 3 halogen atoms; R 2 is methyl or ethyl; W is pentyl, pent-cis-2-enyl or pent-2-ynyl and ~ indicates attachment of the radical to the cyclopropane ring in exo or endo configuration and to the side chain in alpha or beta configuration, are prepared by reacting optically active compounds of the formula or racemates thereof, with ortho esters of the formula</p> |
