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(2R)-2-[(4-ETHYL-2,3-DIOXOPIPERAZINYL)CARBONYLAMINO]-2-PHENYLACETIC ACID CAS63422-71-9Oxygen is used as the third generation of piperazine penicillin side-chain intermediates
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6,7,8,9-TETRAHYDRO-5H-CYCLOHEPTA[B]PYRIDINE CAS7197-96-82,3-Cycloheptenopyridine may be used in chemical synthesis studies