Un compuesto que tiene una fórmula estructural I: o una sal, ester o profármaco del mismo, farmacéuticamente aceptables, en donde los numerales pequeños denotan centros quirales en el compuesto;m se 1-3;R1 es seleccionado del grupo que consiste de (1) hidrógeno,(2) alquilo,(3) carboxaldehído,(4) alcanoil, donde el alcanoil puede ser opcionalmente substituido con hidroxil, y(5) -(CH2 )n CO2 R4 , donde n es 0-6, y R4 es seleccionado del grupo que consiste de (a) hidrógeno,(b) alquilo,(c) cicloalquilo,(d) alquil (cicloalquilo),(e) arilo, y(f) arilalquilo,donde (c) y (d) pueden ser opcionalmente substituidos con 1,2, o 3 sustituyentes independientementeseleccionados del grupo que consiste de(i) alquilo,(ii) alcoxi, y (iii) arilo, ydonde (e) y (f) pueden ser opcionalmente substituidos con 1,2, o 3 substituyentes independientemente seleccionados del grupo que consiste de (i) alquilo,(ii) alcanoil,(iii) alcoxi,(iv) -CO2 R4 ´ donde R4 ´ es seleccionado del grupo que consiste de(a) hidrógeno,(b) alquilo,(c) cicloalquilo,(d) alquilo(cicloalquilo), - 2 -(e) arilo, y(f) arilalquilo,(v) alcanoiloxi,(vi) carboxaldehído,(viii) cicloalquenil(ix) halo,(x) nitro, (xi) perfluoroalquilo,(xii) perfluoroalcoxi(xiii) arisulfonilalquilo,(xiv) ariloilalquiloxicarbonilalquilo,(xv) -NR6 R6´ donde R6 y R6´ son independientemente seleccionados del grupo que consiste de (1´) hidrógeno,(2´) alquilo opcionalmente substituido con alcoxi,(3´) arilo,(4´) arilalquilo, y(5´) un grupo protector nitrógeno(xvi) -SO2 NR6 R6´ donde R6 y R6´ son definidos arriba, y(xvii) -C(O)NR6 R6´ donde R6 y R6´ son definidos arriba;R2 es seleccionado del grupo que consiste de (1) alquilo,(2) cicloalquilo(3) alquilo (cicloalquilo),(4) -C(H)(SR15)(SR15´), donde R15 y R15´ son alquilo, o R15 y R15´ junto con los átomos de azufre a los cuales están unidos, son un anillo 1,3-ditiolano o un anillo 1,3-ditiano.(5) arilo,(6) arilalquilo, y(7) -SR5´ donde R5 es seleccionado del grupo que consiste de (a) alquilo, (b) cicloalquilo,(c) (cicloalquilo)alquilo, y (d) bencilo, donde el bencilo puede ser opcionalmente substituido con 1,2, o 3 substituyentes independientemente seleccionado del grupo que consiste de(i) alquilo,(ii) alcanoil,(iii) alcoxi,(iv) -CO2 R4 , donde R4 es definido arriba,(v) alcanoiloxi,(vi) carboxaldehído(vii) cicloalquilo,(viii) cicloalquenil,(ix) halo,(x) nitro,(xi) perfluoroalquilo,(xii) perfluoroalcoxi,(xiii) -NR6 R6´ donde R6 y R6´ son definidos arriba,(xiv) -SO2 NR6 R6´ donde R6 y R6´ son definidos arriba, y (xv) -C(O)NR6 R6´ donde R6 y R6´ son definidos arriba;R3 es seleccionado del grupo que consiste de (1) un grupo aminoacil opcionalmente acabado con un grupo protector carboxil,(2) -N(R6 )(CH2 )p R7 , donde p es 0-6, R6 es definido arriba, y R7 es seleccionado del grupo que consiste de (a) hidrógeno, (b) alquilo, donde el alquilo puede ser opcionalmente substituido con 1, 2, 3 o 4 substituyentes independientemente seleccionados del grupo que consiste de (i) oxo, (ii) tioxo, (iii) alcoxi, (iv) CO2 R4 , donde R4 es definido arriba, (v) alcanoiloxi, (vi) carboxaldehído, (vii) cicloalquilo, (viii) cicloalquenil, (ix) halo, (x) nitro, (xi) perfluroalquilo, (xii) perfluoroalcoxi, (xiii) NR6 R6´ donde R6 y R6´ son definidos arriba, (xiv) -SO2 NR6 R6´ donde R6 y R6´ son definidos arriba, (xv) -C(O)NR6 R6´ donde R6 y R6´ son definidos arriba, (xvi) arilo, (xvii) hidroxi, y (xviii) heterociclo,(c) cicloalquilo, donde el arilo puede ser opcionalmente substituido con 1,2, o 3 substituyentes independientemente seleccionados del grupo que consiste de (i) alquilo, (ii) halo, (iii) oxo, (iv) arilo,(d) arilo, donde el arilo puede ser opcionalmente substituido con 1, 2, o 3 substituyentes independientemente seleccionados del grupo que consiste de (i) alquilo, (ii) alcanoil, (iii) alcoxi, (iv) CO2 R4 , donde R4 es definido arriba, (v) alcanoiloxi, (vi) carboxaldehído, (vii) cicloalquilo, (viii) cicloalquenil, (ix) halo, (x) nitro, (xi) perfluroalquilo, (xii) perfluoroalcoxi, (xiii) NR6 R6" donde R6 y R6´ son definidos arriba, (xiv) -SO2 ,NR6 R6" donde R6 y R6´ son definidos arriba, (xv) -C(O)NR6 R6" donde R6 y R6´son definidos arriba, (xvi) ariloxi, (xvii) arilalcoxi, (xvi) arilo, (xvii) hidroxi, y (xviii) heterociclo,(e) -CO2 R4 , donde R4 es definido arriba,(f) -CONR6 R8 donde R6 es definido arriba, y R8 es seleccionado del grupo que consiste de (i) hidrógeno, (ii) alquilo, (iii) arilo, y (iv) heterociclo,donde (ii)-(iv) pueden ser opcionalmente substituidos con uno, dos o tres grupos independientemente seleccionados del grupo que consiste de (1´) alquilo, (2´) alcanoil, (3´) alcoxi (4´) CO2 R4 , donde R4 es definido arriba, (5´) alcanoiloxi, (6´) carboxaldehído, (7´) cicloalquilo, (8´) cicloalquenil, (9´) halo, (10´) nitro, (11´) perfluoroalquilo, (12´) perfluoroalcoxi, (13´) NR6 R6" donde R6 y R6´ son definidos arriba (14´) -SO2 NR6 R6" donde R6 y R6´ son definidos arriba,(15´) -C(O)NR6 R6" donde R6 y R6´ son definidos arriba,(16´) ariloxi,(17´) arilalcoxi,(18´) arilo,(19´) hidroxi, y (20´) heterociclo,(g) heterociclo, donde el heterociclo puede ser opcionalmente substituido con uno, dos, o tres grupos independientemente seleccionados del grupo que consiste de (i) alquilo, (ii) alcanoil, (iii) alcoxi, (iv) CO2 R4, donde R4 es definido arriba, (v) alcanoiloxi, (vi) carboxaldehído, (vii) cicloalquilo, (viii) cicloalquenil, (ix) halo, (x) nitro, (xi) perfluoroalquilo, (xii) perfluoroalcoxi, (xiii) NR6R6" donde R6 y R6´ son definidos arriba, (xiv) -SO2 NR6 R6" donde R6 y R6´ son definidos arriba, (xv) -C(O)NR6 R6" donde R6 y R6´ son definidos arriba, (xvi) ariloxi, (xvii) ariloalcoxi, (xviii) arilo, (xix) hidroxi, y (xix) heterociclo, (h) NR6 R8 donde R6 y R8 son definidos arriba, y(i) N(R6 )SO2 R12 , donde R6 es definido previamente y R12 es seleccionado del grupo que consiste de (i) alquilo, (ii) arilo, (iii) arialquilo, (iv) heterociclo, y (v) (heterociclo)alquilo,donde (ii)-(v) puede ser opcionalmente substituido con 1,2, o 3 substituyentes independientemente seleccionados del grupo que consiste de(1´) alquilo,(2´) alcanoil,(3´) alcoxi(4´) CO2 R4 , donde R4 es definido arriba,(5´) alcanoiloxi,(6´) carboxaldehído,(7´) cicloalquilo,(8´) cicloalquenil,(9´) halo,(10´) nitro,(11´) perfluoroalquilo,(12´) perfluoroalcoxi,(13´) NR6 R6´ donde R6 y R6´ son definidos arriba,(14´) -SO2 NR6 R6´ donde R6 y R6´ son definidos arriba,(15´) -C(O)NR6 R6´ donde R6 y R6´ son definidos arriba,(16´) ariloxi,(17´) arilalcoxi,(18´) arilo,(19´) hidroxi, y(20) heterociclo,(3) -O(CH2 )p R7 donde p y R7 son definidos arriba, y(4) -NR20 R21 , donde R20 y R21 , juntos con el átomo de nitrógeno el cual están unidos, son un anillo de 3 a 7 miembros que opcionalmente contiene 1 o 2 enlaces dobles y que opcionalmente contiene una mitad seleccionada del grupo que consiste de (a) oxígeno (b) nitrógeno y (c) -S(O)x- , en donde x es 0-2,donde el anillo formado por R20 y R21 puede ser opcionalmente substituido con 1,2, o 3 substituyentes independientemente seleccionados del grupo que consiste de(1´) alquilo,(2´) alcanoil,(3´) alcoxi(4´) -CO2 R4 , donde R4 es definido arriba,(5´) alcanoiloxi,(6´) carboxaldehído,(7´) cicloalquilo,(8´) cicloalquenil,(9´) halo,(10´) nitro,(11´) perfluoroalquilo,(12´) perfluoroalcoxi,(13´) NR6 R6´ donde R6 y R6´ son definidos arriba,(14´) -SO2 NR6 R6´ donde R6 y R6´ son definidos arriba,(15´) -C(O)NR6 R6´ donde R6 y R6´ son definidos arriba,(16´) ariloxi,(17´) arilalcoxi,(18´) arilo,(19´) hidroxi, y(20´) heterociclo,X es hidroxilo o sulfidrilo; y Y es hidrógeno; oX y Y tomados juntos con el átomo de carbono al cual están atados, forman un carbonil o un tiocarbonil.A compound having a structural formula I: or a pharmaceutically acceptable salt, ester or prodrug thereof, wherein the small numerals denote chiral centers in the compound; m se 1-3; R1 is selected from the group consisting of (1 ) hydrogen, (2) alkyl, (3) carboxaldehyde, (4) alkanoyl, where the alkanoyl can be optionally substituted with hydroxyl, and (5) - (CH2) n CO2 R4, where n is 0-6, and R4 is selected from the group consisting of (a) hydrogen, (b) alkyl, (c) cycloalkyl, (d) alkyl (cycloalkyl), (e) aryl, and (f) arylalkyl, where (c) and (d) can be optionally substituted with 1,2, or 3 substituents independently selected from the group consisting of (i) alkyl, (ii) alkoxy, and (iii) aryl, and where (e) and (f) may be optionally substituted with 1,2, or 3 substituents independently selected from the group consisting of (i) alkyl, (ii) alkanoyl, (iii) alkoxy, (iv) -CO2 R4 'where R4' is selected from the group consisting of (a) hyd halogen, (b) alkyl, (c) cycloalkyl, (d) alkyl (cycloalkyl), - 2 - (e) aryl, and (f) arylalkyl, (v) alkanoyloxy, (vi) carboxaldehyde, (viii) cycloalkenyl (ix ) halo, (x) nitro, (xi) perfluoroalkyl, (xii) perfluoroalkoxy (xiii) arisulfonylalkyl, (xiv) arylalkylalkylcarbonylalkyl, (xv) -NR6 R6 'where R6 and R6' are independently selected from the group consisting of (1 ' ) hydrogen, (2´) alkyl optionally substituted with alkoxy, (3´) aryl, (4´) arylalkyl, and (5´) a nitrogen protecting group (xvi) -SO2 NR6 R6´ where R6 and R6´ are defined above , and (xvii) -C (O) NR6 R6 'where R6 and R6' are defined above; R2 is selected from the group consisting of (1) alkyl, (2) cycloalkyl (3) alkyl (cycloalkyl), (4) -C (H) (SR15) (SR15´), where R15 and R15´ are alkyl, or R15 and R15´ together with the sulfur atoms to which they are attached, are a 1,3-dithiolane ring or a ring 1 , 3-dithian. (5) aryl, (6) arylalkyl, and (7) -SR5 'where R5 is selected from the group consisting of (a) alkyl, (b) cycloalkyl, (c) (cycloalkyl) alkyl, and (d) benzyl, where the benzyl can be optionally substituted with 1,2, or 3 substituents independently selected from the group consisting of (i) alkyl , (ii) alkanoyl, (iii) alkoxy, (iv) -CO2 R4, where R4 is defined above, (v) alkanoyloxy, (vi) carboxaldehyde (vii) cycloalkyl, (viii) cycloalkenyl, (ix) halo, (x ) nitro, (xi) perfluoroalkyl, (xii) perfluoroalkoxy, (xiii) -NR6 R6´ where R6 and R6´ are defined above, (xiv) -SO2 NR6 R6´ where R6 and R6´ are defined above, and (xv) -C (O) NR6 R6 'where R6 and R6' are defined above; R3 is selected from the group consisting of (1) an aminoacyl group optionally terminated with a carboxy protecting group, (2) -N (R6) (CH2) p R7, where p is 0-6, R6 is defined above, and R7 is selected from the group consisting of (a) hydrogen, (b) alkyl, where the alkyl can be optionally substituted with 1, 2, 3 or 4 substituents independently selected from the group you are te (i) oxo, (ii) thioxo, (iii) alkoxy, (iv) CO2 R4, where R4 is defined above, (v) alkanoyloxy, (vi) carboxaldehyde, (vii) cycloalkyl, (viii) cycloalkenyl, ( ix) halo, (x) nitro, (xi) perfluroalkyl, (xii) perfluoroalkoxy, (xiii) NR6 R6´ where R6 and R6´ are defined above, (xiv) -SO2 NR6 R6´ where R6 and R6´ are defined above , (xv) -C (O) NR6 R6 'where R6 and R6' are defined above, (xvi) aryl, (xvii) hydroxy, and (xviii) heterocycle, (c) cycloalkyl, where the aryl can be optionally substituted with 1,2, or 3 substituents independently selected from the group consisting of (i) alkyl, (ii) halo, (iii) oxo, (iv) aryl, (d) aryl, where the aryl can be optionally substituted with 1, 2 , or 3 substituents independently selected from the group consisting of (i) alkyl, (ii) alkanoyl, (iii) alkoxy, (iv) CO2 R4, where R4 is defined above, (v) alkanoyloxy, (vi) carboxaldehyde, (vii ) cycloalkyl, (viii) cycloalkenyl, (ix) halo, (x) nitro, (xi) per fluroalkyl, (xii) perfluoroalkoxy, (xiii) NR6 R6 "where R6 and R6´ are defined above, (xiv) -SO2, NR6 R6" where R6 and R6´ are defined above, (xv) -C (O) NR6 R6 "where R6 and R6 'are defined above, (xvi) aryloxy, (xvii) arylalkoxy, (xvi) aryl, (xvii) hydroxy, and (xviii) heterocycle, (e) -CO2 R4, where R4 is defined above, ( f) -CONR6 R8 where R6 is defined above, and R8 is selected from the group consisting of (i) hydrogen, (ii) alkyl, (iii) aryl, and (iv) heterocycle, where (ii) - (iv) can be optionally substituted with one, two or three groups independently selected from the group consisting of (1´) alkyl, (2´) alkanoyl, (3´) alkoxy (4´) CO2 R4, where R4 is defined above, (5´ ) alkanoyloxy, (6´) carboxaldehyde, (7´) cycloalkyl, (8´) cycloalkenyl, (9´) halo, (10´) nitro, (11´) perfluoroalkyl, (12´) perfluoroalkoxy, (13´) NR6 R6 "where R6 and R6´ are defined above (14´) -SO2 NR6 R6" where R6 and R6´ are defined above, (15´) -C (O) NR6 R6 "don of R6 and R6´ are defined above, (16´) aryloxy, (17´) arylalkoxy, (18´) aryl, (19´) hydroxy, and (20´) heterocycle, (g) heterocycle, where the heterocycle can be optionally substituted with one, two, or three groups independently selected from the group consisting of (i) alkyl, (ii) alkanoyl, (iii) alkoxy, (iv) CO2 R4, where R4 is defined above, (v) alkanoyloxy, ( vi) carboxaldehyde, (vii) cycloalkyl, (viii) cycloalkenyl, (ix) halo, (x) nitro, (xi) perfluoroalkyl, (xii) perfluoroalkoxy, (xiii) NR6R6 "where R6 and R6 'are defined above, (xiv ) -SO2 NR6 R6 "where R6 and R6´ are defined above, (xv) -C (O) NR6 R6" where R6 and R6´ are defined above, (xvi) aryloxy, (xvii) ariloalkoxy, (xviii) aryl, (xix) hydroxy, and (xix) heterocycle, (h) NR6 R8 where R6 and R8 are defined above, and (i) N (R6) SO2 R12, where R6 is previously defined and R12 is selected from the group consisting of ( i) alkyl, (ii) aryl, (iii) arialkyl, (iv) heterocycle, and (v) (heterocycle) alkyl, d where (ii) - (v) may be optionally substituted with 1.2, or 3 substituents independently selected from the group consisting of (1´) alkyl, (2´) alkanoyl, (3´) alkoxy (4´) CO2 R4 , where R4 is defined above, (5´) alkanoyloxy, (6´) carboxaldehyde, (7´) cycloalkyl, (8´) cycloalkenyl, (9´) halo, (10´) nitro, (11´) perfluoroalkyl, ( 12´) perfluoroalkoxy, (13´) NR6 R6´ where R6 and R6´ are defined above, (14´) -SO2 NR6 R6´ where R6 and R6´ are defined above, (15´) -C (O) NR6 R6 ´ where R6 and R6´ are defined above, (16´) aryloxy, (17´) arylalkoxy, (18´) aryl, (19´) hydroxy, and (20) heterocycle, (3) -O (CH2) p R7 where p and R7 are defined above, and (4) -NR20 R21, where R20 and R21, together with the nitrogen atom which are attached, are a 3 to 7 member ring that optionally contains 1 or 2 double bonds and that optionally It contains a selected half of the group consisting of (a) oxygen (b) nitrogen and (c) -S (O) x-, where x is 0-2, where the ring formed by R20 and R21 can be optionally substituted with 1,2, or 3 substituents independently selected from the group consisting of (1´) alkyl, (2´) alkanoyl, (3´) alkoxy (4´) -CO2 R4, where R4 is defined above, (5´) alkanoyloxy, (6´) carboxaldehyde, (7´) cycloalkyl, (8´) cycloalkenyl, (9´) halo, (10´) nitro, (11´) perfluoroalkyl, (12´ ) perfluoroalkoxy, (13´) NR6 R6´ where R6 and R6´ are defined above, (14´) -SO2 NR6 R6´ where R6 and R6´ are defined above, (15´) -C (O) NR6 R6´ where R6 and R6´ are defined above, (16´) aryloxy, (17´) arylalkoxy, (18´) aryl, (19´) hydroxy, and (20´) heterocycle, X is hydroxyl or sulfydryl; and Y is hydrogen; oX and Y taken together with the carbon atom to which they are attached, form a carbonyl or a thiocarbonyl.