| porphin | <protein> A cyclic tetrapyrrole in which the four pyrrole groups are linked by their alpha-carbon atoms via methene (-CH=) bridges, porphin is the partial compund of porphyrins. (14 Oct 1997) |
|---|---|
| porphine | The unsubstituted cyclic tetrapyrrole nucleus that is the basis of the porphyrins. See: porphyrins. Compare: chlorin, phorbin, corrin. Synonym: porphyrin. (05 Mar 2000) |