efavirenz [ 6-chloro-4-cyclopropylethynyl-4-trifluoromethyl-1,4-dihydro-2H-3,1-benzoxazin-2-one,DMP-266,L 743726,Bristol-Myers Squibb brand of efavirenz,DMP 266,Du Pont brand of efavirenz,L 743,726,L-743,726,L-743726,Merck Sharp & Dohme brand of efavirenz,Stocrin,Sustiva,United Drug brand of efavirenz,efavirenz, (R)-isomer,efavirenz, (S)-isomer ] HIV-1 reverse transcriptase inhibitor; RN given for (+-)-isomer; L-743,726 is the (S)-isomer; structure in first source