Compounds as anti-tubercular agents

1. A compound of structural Formula (1) or a salt, hydrate or stereoisomer thereof:

wherein

X is NH;

R 1 is hydrogen;

R 2 is selected from the group consisting of hydrogen, hydroxyl, C 1-10 alkyl, and C 1-6 alkoxy;

R3 is selected from the group consisting of:

R 4 is selected from the group consisting of hydrogen, deuterium, halogen, C 1-6 straight chain or branched chain alkyl, C 1-6 alkoxy, amino, NH(alkyl), and N(alkyl) 2 ;

R 6 and R 7 are independently selected from the group consisting of hydrogen, C 1-10 alkyl, —COR 8 , —CH 2 OCOR 8 , —CH 2 OCONHR 8 R 9 , —COOR 8 , —CONR 8 R 9 , —SO 2 R 8 , phenyl, and benzyl;

R 8 and R 9 are independently selected from the group consisting of hydrogen and C 1-6 straight chain or branched chain alkyl;

n is 1, 2 or 3;

wherein said compound is selected from the group consisting of:

i. N-((S)-1-Benzylpiperidin-3-yl)-2-hydroxy-2-phenylacetamide;

ii. N-((R)-1-Benzylpiperidin-3-yl)-2-hydroxy-2-phenylpropanamide;

iii. (S)-2-Hydroxy-N-(1-methylpiperidin-4-yl)-2-phenylacetamide;

iv. (R)-2-Hydroxy-N-(1-methylpiperidin-4-yl)-2-phenylacetamide;

v. (R)-2-Hydroxy-N-((R)-1-methylpiperidin-3-yl)-2-phenylacetamide;

vi. (R)-2-Hydroxy-N-((S)-1-methylpiperidin-3-yl)-2-phenylacetamide;

vii. (R)-N-(1-Benzylpiperidin-4-yI)-2-hydroxy-2-phenylacetamide;

viii. (S)-N-(1-Benzy Ipiperidin-4-yl)-2-hydroxy-2-phenylacetamide;

ix. (R)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

x. (S)-2-Hydroxy-N-((R)-1-methylpiperidin-3-yl)-2-phenylacetamide;

xi. (S)-2-Hydroxy-N-((S)-1-methylpiperidin-3-yl)-2-phenylacetamide;

xii. (R)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xiii. 2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xiv. (S)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xv. (S)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xvi. 2-(3-Bromo-2,6-difluorophenyl)-2-hydroxy-N-(piperidin-4-yl)acetamide; and

xvii. (R)-Ethyl 4-(2-methoxy-2-phenylacetamido)piperidine-1-carboxylate.

2. The compound of claim 1 , wherein said compound is selected from the group consisting of:

i. (R)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

ii. 2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

iii. (S)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

iv. (S)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

v. 2-(3-Bromo-2,6-difluorophenyl)-2-hydroxy-N-(piperidin-4-yl)acetamide; and

vi. (R)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide.

3. A process for preparing the compound of claim 1 having structural Formula (1) or a salt, hydrate or stereoisomer thereof, comprising:

coupling of compound A with a coupling agent (i) in presence of an organic solvent

wherein

X is NH;

R 1 is hydrogen;

R 2 is selected from the group consisting of hydrogen, hydroxyl, C 1-10 alkyl, and C 1-6 alkoxy;

R3 is selected from the group consisting of:

R 4 is selected from the group consisting of hydrogen, deuterium, halogen, C 1-6 straight chain or branched chain alkyl, C 1-6 alkoxy, amino, NH(alkyl), and N(alkyl) 2 ;

R 6 and R 7 are independently selected from the group consisting of hydrogen, C 1-10 alkyl, —COR 8 , —CH 2 OCOR 8 , —CH 2 OCONHR 8 R 9 , —COOR 8 , —CONR 8 R 9 , —SO 2 R 8 , phenyl, and benzyl;

R 8 and R 9 are independently selected from the group consisting of hydrogen and C 1-6 straight chain or branched chain alkyl;

N is 1, 2 or 3;

wherein said compound is selected from the group consisting of:

i. N-(S)-1-Benzylpiperidin-3-yl)-2-hydroxy-2-phenylacetamide;

ii. N-((R)-1-Benzylpiperidin-3-yl)-2-hydroxy-2-phenylpropanamide;

iii. (S)-2-Hydroxy-N-(1-methylpiperidin-4-yl)-2-phenylacetamide;

iv. (R)-2-Hydroxy-N-(1-methylpiperidin-4-yl)-2-phenylacetamide;

v. (R)-2-Hydroxy-N-((R)-1-methylpiperidin-3-yl)-2-phenylacetamide;

vi. (R)-2-Hydroxy-N-((S)-1-methylpiperidin-3-yl)-2-phenylacetamide;

vii. (R)-N-(1-Benzylpiperidin-4-yl)-2-hydroxy-2-phenylacetamide;

viii. (S)-N-(1-Benzylpiperidin-4-yl)-2-hydroxy-2-phenylacetamide;

ix. (R)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

x. (S)-2-Hydroxy-N-((R)-1-methylpiperidin-3-yl)-2-phenylacetamide;

xi. (S)-2-Hydroxy-N-((S)-1-methylpiperidin-3-yl)-2-phenylacetamide;

xii. (R)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xiii. 2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xiv. (S)-2-Hydroxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xv. (S)-2-Methoxy-2-phenyl-N-(piperidin-4-yl)acetamide;

xvi. 2-(3-Bromo-2,6-difluorophenyl)-2-hydroxy-N-(piperidin-4-yl)acetamide; and

xvii. (R)-Ethyl 4-(2-methoxy-2-phenylacetamido)piperidine-1-carboxylate.

4. The compound of claim 1 in combination with an additional agent selected from the group consisting of cycloserine, amikacin, linezolid, ethambutol, rifampicin, isoniazid, ethionamide, moxyfloxacin, clarithromycin, PAS, clofazamine, streptomycin, capreomycin, and kanamycin.

5. A pharmaceutical composition comprising the compound of claim 1 and a pharmaceutically acceptable excipient.

6. The pharmaceutical composition of claim 5 , further comprising one or more additional agent selected from the group consisting of cycloserine, amikacin, linezolid, ethambutol, rifampicin, isoniazid, ethionamide, moxyfloxacin, clarithromycin, PAS, clofazamine, streptomycin, capreomycin, and kanamycin.