Two new indole alkaloids, 20-epi-antirhine [4] and 13(S)-hydroxydihydrocorynantheol [6], have been isolated from Antirhea portoricensis (Rubiaceae), collected in the Caribbean. Structures have been established on the basis of spectral data. In addition, four known alkaloids have been isolated, namely, yohimbol [1], epi-yohimbol [2], antirhine [3] and iso-antirhine [5].