9α-Bromo analog of beclometasone dipropionate monohydrate

In the crystal structure of (8S,9R,10S,11S,13S,14S,16S,17R)-9α-bromo-11-hydroxy-10,13,16-trimethyl-3-oxo-17-[2-(propionyloxy)acetyl]-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-17-yl propionate monohydrate, C28H37BrO7·H2O, which has a 9α-Br atom in place of the 9α-Cl atom of monohydrated beclometasone dipropionate, one six-membered ring is planar (r.m.s. deviation = 0.02 ) owing to its 1,4-diene-3-one composition, whereas the two other six-membered rings each have a chair conformation. The organic molecule and water molecules engage in hydrogen-bonding interactions, generating a helical chain running along the c axis of the orthorhombic unit cell.