. . "1915Z"^^ . . "American chemist" . "1992-03-21Z"^^ . . . "John Clark Sheehan (23 September 1915 \u2013 21 March 1992) was an American organic chemist whose work on synthetic penicillin led to tailor-made forms of the drug. After nine years of hard work at the Massachusetts Institute of Technology (M.I.T.), he became the first to discover a practical method for synthesizing penicillin V."@en . "Sheehan, John C."@en . . . . "1992Z"^^ . "1915-09-23Z"^^ . . . . . . "John Clark Sheehan"@en . .