L-(+)-Cysteine → HCID 29719, compound

Participants

Reaction Steps

The other pathway from dopaquinone to melanin involves the addition of cysteine to dopaquinone to produce 5-S-cysteinyldopa, followed by the oxidation of 5-S-cysteinyldopa to 5-S-cysteinyldopaquinone. A ring closure of the 5-S-cysteinyldopaquinone then yields 7-alanyl-5-hydroxy-3-carboxy-2H-1,4-benzothiazine which is subsequently decarboxylated to yield 7-alanyl-5-hydroxy-2H-1,4-benzothiazine. At this point, the 7-alanyl-5-hydroxy-2H-1,4-benzothiazine is converted to melanin and pheomelanin. Tyrosinase does not play any additional role in this melanin production pathway.

Provenance & Evidence