David R. Andrews

Imidazolylsulfonates: electrophilic partners in cross-coupling reactions.

Aryl imidazolylsulfonates participate as electrophilic coupling partners in palladium-mediated cross-coupling reactions. The aryl imidazolylsulfonates display good stability while maintaining good reactivity in a variety of palladium-catalyzed coupling reactions. Imidazolylsulfonates are a practical and economic alternative to triflates.

Reaction of aziridinium ions with organometallic reagents: optimization of the key step of ecopipam synthesis

Formation, stability and reactivity of aziridinium ions 3 towards organometallic reagents was explored and optimized for the efficient preparation of key drug intermediate 5c.

A corticoid synthesis from 9α-hydroxyandrost-4-ene-3,17-dione via a steroidal allene

Abstract An alternative synthesis of 17α, 21-dihydroxy-16β-methylpregna-4,9(11)-diene-3,20-dione, an intermediate to the potent anti-inflammatory corticoid, Betamethasone, is described. The key reactions are the bis epoxidation of a C-17,20 allene and the regiospecific elimination of a 9α-methyl carbonate.

A corticoid synthesis from 9α-hydroxyandrost-4-ene-3,17-dione via a steroidal oxazoline

The synthesis of 21-acetoxy-17α-hydroxy-16β-methylpregna-1,4,9(11)-triene from 9α-hydroxyandrost-4-ene-3,17-dione via a 17-cyanohydrin and a 17-oxazoline is described.