We don't have synonyms for carpaine yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are carmine, carping and caprine.
(n) :
(organic chemistry) A macrolide antibiotic, (1S,11R,13S,14S,24R,26S)-13,26-dimethyl-2,15-dioxa-12,25-diazatricyclo[22.2.2.211,14]triacontane-3,16-dione, found in Carica papaya
(n) :
(organic chemistry) A macrolide antibiotic, (1S,11R,13S,14S,24R,26S)-13,26-dimethyl-2,15-dioxa-12,25-diazatricyclo[22.2.2.211,14]triacontane-3,16-dione, found in Carica papaya