It is shown that in so far as hydride reductions are concerned the following order of steric hindrance can be stated: two 1,3-diaxial peri one 1,3-diaxial. An alternate route is described to quassin synthon 2 from Diels-Alder adduct 1 in eleven steps. ... Telraheilrrn Vol 39. No :3. pp 39:9 10 393?. 1983 Pnnlcd in Grcal Bnlain 004(M020'83 S3 00 + 00 PergatTlon Press Ltd AN ALTERNATE ROUTE TO A QUASSIN SYNTHON COMPARISON OF 1,3-DIAXIAL AND PERI STERIC ...