A compound of structural formula I: including tautomers or pharmaceutically acceptable salts and individual enantiomers and diastereomers thereof wherein: A represents hydrogen, or C 1-6 alkyl, said alkyl optionally substituted with 1 to 3 groups of halo, OH, or Oalkyl; X represents hydrogen, OH, halo, OC 1-6 alkyl, NR 2 R 3, or (CH 2) n C 6-10 aryl, said alkyl and aryl optionally substituted with 1 to 3 groups of R a; R1 represents C 6-10 aryl, or (CH 2) n C 5-10 heterocyclyl, said aryl and heterocyclyl substituted with 1 to 3 groups of R a; R 2 and R 3 independently represent H, OH, C 1-6 alkyl, N(CH 3) 2, (CH 2) n C 5-10 heterocyclyl, or (CH 2) n C 6-10 aryl, said aryl and heterocyclyl optionally substituted with 1 to 3 groups of R a; or R 2 and R 3 together with the nitrogen atom to which they are attached form a 5-10 membered ring that is optionally substituted with 1 to 3 groups of halo, OH, C 2-6 alkenyl, (CH 2) n C 5-10 heterocyclyl or (CH 2) n C 6-10 aryl; R a represents C 1-6 alkyl, halogen, hydroxyl, C 2-4 alkynyl, (CH 2) n CF 3, OCHF 2, OCF 3, C 3-6 cycloalkyl, O(CH 2) n C 3-6 cycloalkyl, NR 2 C R 2, C N(R 2) 2, C(R 2) 2 OR 2, C R 2, NO 2, CN, N(R 2) 2, (CH 2) n C OR 2, SO 2 R 2, NHSO 2 R 2, OC 1-6 alkyl, O(CH 2) n C 5-10 heterocyclyl, NH(CH 2) n C 5-10 heterocyclyl, (CH 2) n C 6-10 aryl, O(CH 2) n C 6-10 aryl, or O(CH 2) n C 5-10 heterocyclyl, said alkyl, alkynyl, cycloalkyl, heterocyclyl and aryl optionally substituted with 1 to 3 groups of R b; R b represents C 1-6 alkyl, OC 1-6 alkyl, halogen, CHF 2, OCHF 2, -O-, N(R 2) 2, CH 2 OH, S 2 NR 2 R 3, (CH 2) n C 6-10 aryl, (CH 2) n C 5-10 heterocyclyl, C (CH 2) n C 5-10 heterocyclyl, NH(CH 2) n C 5-10 heterocyclyl, C NHC 3-6 cycloalkyl, OR 2, C 3-6 cycloalkyl, (CH 2) n CF 3, or CN, said heterocyclyl optionally substituted with 1 or more of C 1-6 alkyl; and n represents 0 to 5. A represents hydrogen, or C 1-6 alkyl, said alkyl optionally substituted with 1 to 3 groups of halo, OH, or Oalkyl; X represents hydrogen, OH, halo, OC 1-6 alkyl, NR 2 R 3, or (CH 2) n C 6-10 aryl, said alkyl and aryl optionally substituted with 1 to 3 groups of R a; R1 represents C 6-10 aryl, or (CH 2) n C 5-10 heterocyclyl, said aryl and heterocyclyl substituted with 1 to 3 groups of R a; R 2 and R 3 independently represent H, OH, C 1-6 alkyl, N(CH 3) 2, (CH 2) n C 5-10 heterocyclyl, or (CH 2) n C 6-10 aryl, said aryl and heterocyclyl optionally substituted with 1 to 3 groups of R a; or R 2 and R 3 together with the nitrogen atom to which they are attached form a 5-10 membered ring that is optionally substituted with 1 to 3 groups of halo, OH, C 2-6 alkenyl, (CH 2) n C 5-10 heterocyclyl or (CH 2) n C 6-10 aryl; R a represents C 1-6 alkyl, halogen, hydroxyl, C 2-4 alkynyl, (CH 2) n CF 3, OCHF 2, OCF 3, C 3-6 cycloalkyl, O(CH 2) n C 3-6 cycloalkyl, NR 2 C R 2, C N(R 2) 2, C(R 2) 2 OR 2, C R 2, NO 2, CN, N(R 2) 2, (CH 2) n C OR 2, SO 2 R 2, NHSO 2 R 2, OC 1-6 alkyl, O(CH 2) n C 5-10 heterocyclyl, NH(CH 2) n C 5-10 heterocyclyl, (CH 2) n C 6-10 aryl, O(CH 2) n C 6-10 aryl, or O(CH 2) n C 5-10 heterocyclyl, said alkyl, alkynyl, cycloalkyl, heterocyclyl and aryl optionally substituted with 1 to 3 groups of R b; R b represents C 1-6 alkyl, OC 1-6 alkyl, halogen, CHF 2, OCHF 2, -O-, N(R 2) 2, CH 2 OH, S 2 NR 2 R 3, (CH 2) n C 6-10 aryl, (CH 2) n C 5-10 heterocyclyl, C (CH 2) n C 5-10 heterocyclyl, NH(CH 2) n C 5-10 heterocyclyl, C NHC 3-6 cycloalkyl, OR 2, C 3-6 cycloalkyl, (CH 2) n CF 3, or CN, said heterocyclyl optionally substituted with 1 or more of C 1-6 alkyl; and n represents 0 to 5.