(1-Isopropenyl-4,7,10-trimethyl-2,3,4,4a,5,6,7,7a,8,9-decahydro-1H-benzo[d]naphthalen-7-yl)(methylidyne)-.lambda.~5~-azane 7-Isocyanoneoamphilecta-11,15-diene AIDS-142731 AIDS142731 NSC660370