The Molecular and Crystal Structure of Buprenorphine Hydrochloride, a Morphine Analogue

The structure of buprenorphine hydrochloride {(6 R ,7 R ,14 S )-17-cyclopropylmethyl-7,8-dihydro- 7-[(1 S )-1-hydroxy-1,2,2-trimethylpropyl]- 6- O -methyl-6,14-ethano-17-normorphine hydrochloride} was solved by direct methods and refined anisotropically to the R value of 0.062 for 3 049 observed reflections. The substance crystallizes in the tetragonal space group P4 3 2 1 2 , a = b = 11.513(2) Å, c = 42.054(8) Å, V = 5 574(2) Å 3 , Z = 8, D calc = 1.201 g cm -3 , μ(MoKα) = 0.17 mm -1 . The compound is the first morphine derivative with a 6,14-ethano bridge whose molecular structure has been solved.