A short, protecting group-free total synthesis of bruceollines D, E, and J.

A short, protecting group-free total synthesis of bruceollines D, E, and J has been achieved. The enantioselective reduction of bruceolline E with β-chlorodiisopinocampheylborane delivers both the natural and unnatural enantiomers of bruceolline J in excellent yields and enantioselectivities. Reduction with baker's yeast and sucrose was shown to provide the unnatural enantiomer of bruceolline J in 98% ee.

3,3-Dimethyl-1,2,3,4-tetra-hydro-cyclo-penta-[b]indole-1,2-dione (bruceolline E).

The title compound, C(13)H(11)NO(2), crystallizes with two mol-ecules in the asymmetric unit. The crystal packing is stabilized by N-H⋯O hydrogen bonds, which link the mol-ecules into chains along [10[Formula: see text]], and weak C-H⋯O inter-actions.

4-Phenyl-sulfon-yl-2-(p-tolyl-sulfon-yl)-1H,8H-pyrrolo-[2,3-b]indole.

The title compound, C(23)H(18)N(2)O(4)S(2), contains a pyrrolo group fused onto the plane of an indole ring with phenyl-sulfonyl and p-toluene-sulfonyl groups bonded to the indole and pyrrolo rings. The angles between the mean planes of the pyrrolo-indole ring and the phenyl-sulfonyl and p-toluene-sulfonyl rings are 73.7 (6) and 80.