A process for preparing a compound of formula or a salt thereof, the process comprising (a) reacting a compound of formula with a compound of formula to obtain a compound of formula (b) deprotecting the compound formed in step (a) to obtain a compound of formula; and (c) optionally converting the compound of formula to a salt thereof, wherein each occurrence of R is independently selected from hydrogen, hydroxy, halogen, carboxyl, cyano, nitro, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted cycloalkenylalkyl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted heterocyclylalkyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroarylalkyl, -COOR x, -C R x, -C R x, - C NR x R y, -C ONR x R y, -NR x R y, -NR x CONR x R y, -N(R x)SOR x, - N(R x)SO 2 R y, -(=N-N(R x)R y), -NR x C OR y, -NR x C R y -, -NR x C R y, - NR x C NR x R y, -SONR x R y, -SO 2 NR x R y, -OR x, -OR X C NR x R y, - OR x C OR x, -OC R x, -OC NR x R y, -R x NR y C R z, -R x OR y, -R x C OR y, - R x C NR x R y, -R x C R y, -R x OC R y, -SR x, -SOR x, -SO 2 R x, and -ONO 2, wherein each occurrence of R x, R y and R z is independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroarylalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted heterocyclic ring, substituted or unsubstituted heterocyclylalkyl ring, or substituted or unsubstituted amino, or (i) any two of R x and R y, when bound to a common atom, are joined to form a substituted or unsubstituted, saturated or unsaturated 3-14 membered ring, which may optionally include heteroatoms which may be the same or different and are selected from O, NR z or S, or (ii) any two of R x and R y, when bound to a common atom, are joined to form an oxo (=O), thio (=S) or imino (=NR f) (wherein R f is hydrogen or substituted or unsubstituted alkyl); R 1 is substituted or unsubstituted C 1-6 alkyl; Cy 1 is a monocyclic or bicyclic group selected from substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclic group, substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl; Pg is a protecting group; and n is an integer selected from 0, 1, 2, 3 or 4. (a) reacting a compound of formula with a compound of formula to obtain a compound of formula (b) deprotecting the compound formed in step (a) to obtain a compound of formula; and (c) optionally converting the compound of formula to a salt thereof, each occurrence of R is independently selected from hydrogen, hydroxy, halogen, carboxyl, cyano, nitro, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted cycloalkenylalkyl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted heterocyclylalkyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroarylalkyl, -COOR x, -C R x, -C R x, - C NR x R y, -C ONR x R y, -NR x R y, -NR x CONR x R y, -N(R x)SOR x, - N(R x)SO 2 R y, -(=N-N(R x)R y), -NR x C OR y, -NR x C R y -, -NR x C R y, - NR x C NR x R y, -SONR x R y, -SO 2 NR x R y, -OR x, -OR X C NR x R y, - OR x C OR x, -OC R x, -OC NR x R y, -R x NR y C R z, -R x OR y, -R x C OR y, - R x C NR x R y, -R x C R y, -R x OC R y, -SR x, -SOR x, -SO 2 R x, and -ONO 2, wherein each occurrence of R x, R y and R z is independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted arylalkyl, substituted or unsubstituted heteroaryl, substituted or unsubstituted heteroarylalkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted cycloalkenyl, substituted or unsubstituted heterocyclic ring, substituted or unsubstituted heterocyclylalkyl ring, or substituted or unsubstituted amino, or (i) any two of R x and R y, when bound to a common atom, are joined to form a substituted or unsubstituted, saturated or unsaturated 3-14 membered ring, which may optionally include heteroatoms which may be the same or different and are selected from O, NR z or S, or (ii) any two of R x and R y, when bound to a common atom, are joined to form an oxo (=O), thio (=S) or imino (=NR f) (wherein R f is hydrogen or substituted or unsubstituted alkyl); R 1 is substituted or unsubstituted C 1-6 alkyl; Cy 1 is a monocyclic or bicyclic group selected from substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocyclic group, substituted or unsubstituted aryl and substituted or unsubstituted heteroaryl; Pg is a protecting group; and n is an integer selected from 0, 1, 2, 3 or 4.