1,15,17,17-Tetra(1-aziridinyl)-2,5,8,11,14-pentaoxa-16,18,19-triaza-1.lambda.~5~,15.lambda.~5~,17.lambda.~5~-triphosphabicyclo[13.3.1]nonadeca-1(19),15,17-triene AIDS-149096 AIDS149096 NSC682802