An Unusual 3H-Pyrrole at 150K

Most pyrroles are observed to form the 1H-tautomer; here we report the structure of a rare example of a 3H-pyrrole, trimethyl 6-oxo-5,5a,10b,10c-tetrahydro-3H-pyrrolizino[1,2-e]indole-4,5, 10b-tricarboxylate, C₁₉H₁₈N₂O₇. The molecules pack as dimers linked via bifurcated hydrogen bonds.

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