1,3,4,5-Tetrahydrobenzo[cd]indole-5-one

3,4-Dihydrobenz[cd]indol-5(1H)-one is an Indole (I577320)-containing compound commonly used as an intermediate to prepare ergot alkaloids (e.g. Ergotamine Tartrate [E599500]), compounds that are used to treat migranes. 3,4-Dihydrobenz[cd]indol-5(1H)-one is also used as a reagent to synthesize Rugulovasine A, a mycotoxin that is produced by Penicillin crateriforme.

Journal of the American Chemical Society, 71, p. 761, 1949 DOI: 10.1021/ja01171a001
Tetrahedron Letters, 26, p. 4183, 1985 DOI: 10.1016/S0040-4039(00)98986-X