Supporting information

Pharmacophore based discovery of DHPM based muscarinic

receptor antagonist

B N Acharya, G B Dharma Rao, Deo Kumar, Praveen Kumar and M P Kaushik

Defence R&D Establishment, Jhansi Road, Gwalior 474002, MP, India

Contents

1. Synthesis procedure 2

2. Table S1. Structure and analytical data of DHPM based molecules 3-4

2. 1H NMR spectra of DHPMs 5-10

3. 13C NMR spectra of DHPMs 11-16

* B. N. AcharyaDefence R&D EstablishmentJhansi RoadGwalior-474002, Indiabnacharya@drde.drdo.in

1

Synthesis of N, N-dimethylaminoethylacetoacetate

In a typical experimental procedure (Rao et al. 2013), a 50 ml round bottomed flask equipped

with a reflux condenser was charged with a homogenous mixture of N.N-

dimethylaminoethanol (4.5 mmol) and methylacetoacetate (3 mmol) and heated at 1100C.

The progress of the reaction was monitored byTLC. After completion of reaction, the

required product, N,N-dimethylaminoethylacetoacetate was purified by silica gel column

chromatography using light petroleum ether and ethylacetate and subsequently used in

Biginelli reaction for DHPM synthesis.

Synthesis of dihydropyrimidine dinones (DHPMs)

A 50 ml round bottomed flask equipped with a reflux condenser was charged with

arylaldehyde (1.0 mmol) and urea/thiourea (1.5 mmol). The precursors were finely powdered

and mixed together and allowed to stir for 30min at room temperature. Subsequently N,N-

dimethylaminoethylacetoacetate (1.5 mmol) were added. The resulting reaction mixture was

heated at 110˚C (oil bath) with constant stirring till the reaction was completed. The progress

of reaction was monitored by TLC using CHCl3:CH3OH (8:2) with two drops of ammonia

solution as a mobile phase. After completion of reaction as indicated on TLC, the contents of

reaction mixture was cooled to room temperature and the crude reaction mixture was crushed

and dissolved in 10ml of 2N HCl (1.8ml in 10ml of H2O). The reaction mixture was washed

with ethylacetate and the aqueous part was neutralized with 10 ml of 2N NaOH. Then

product was extracted by ethylacetate and evaporated at reduced pressure. The obtained crude

solid mass was washed with cold diethylether (15 ml x 3) to remove any unreacted reactants

to afford the pure desired product. All the synthesized dihydropyrimidine dinone (DHPM)

products were characterized and confirmed by spectroscopic techniques.

Synthesis of methyl iodide salts of DHPMs

In a separate experiment, commercially available methyl iodide (b.p = 42.5˚C, 1.5 eq) was

added drop wise to above DHPMs (1.0 eq) in dry acetone in an ice-bath. After complete

addition of the methyl iodide, the resultant reaction mixture was stirred for one hour at room

temperature. The solid salt form of Biginelli’s product was separated out by simple filtration,

washed with dry acetone (5ml x 3) and dried at reduced pressure to remove acetone.

2

Table S1. Structure and analytical data of DHPM based molecules

Code/Structure Characterization dataDHPM1 2-(dimethylamino)ethyl-6-methyl-4-(4-ethoxyphenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-

carboxylate: Yield (%): 65, m.p (0C): 178-180. IR (KBr, νMax cm-1) = 3241, 3111, 2973, 2770, 1724, 1706, 1650, 1612, 1513, 1460, 1390, 1225, 1048, 955, 793. 1H-NMR (400MHz, CDCl3): δ 1.374-1.357 (t, J = 6.8Hz, 3H), 2.167 (s, 6H), 2.300 (s, 3H), 2.423-2.438(t, J = 6.0Hz, 2H), 3.990-3.973 (q, J = 6.8Hz, 2H), 4.075-4.090 (t, J = 6.0Hz, 2H), 5.311 (s, 1H), 5.660 (s, 1H), 6.765-6.786 (d, J = 8.4Hz, 2H), 7.176-7.197 (d, J = 8.4Hz, 2H), 8.016 (s, 1H). 13C NMR (CDCl3): δ = 14.940, 18.857, 45.770, 55.309, 57.862, 62.006, 63.611, 101.613, 114.745, 127.944, 136.022, 146.375, 153.260, 158.808, 165.785, ESI-MS: m/z = 348.

DHPM2 2-(dimethylamino)ethyl-6-methyl-4-(4-nitrophenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-carboxylate: Yield (%): 58, m.p (0C): 148-150. IR (KBr, νMax) = 3237, 3114, 2947,2773, 1705, 1644, 1523, 1348, 1223, 1100, 953, 789. 1H-NMR (400MHz, CDCl3): δ 2.209 (s, 6H), 2.360 (s, 3H), 2.474-2.485 (t, J = 4.4Hz, 2H), 4.146-4.157 (t, J = 4.4Hz, 2H), 5.529 (s, 1H), 6.197 (s, 1H), 7.554-7.533 (d, J = 8.4Hz, 2H), 8.145 (s, 1H), 8.180-8.159 (d, J = 8.4Hz, 2H). 13C NMR (CDCl3): δ = 18.876, 45.494, 55.020, 57.756, 61.868, 100.373, 124.016, 127.595, 147.505, 147.557, 150.406, 152.961, 165.153. ESI-MS: m/z=349.574.

DHPM3 2-(dimethylamino)ethyl-6-methyl-4-(4-methylphenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-carboxylate: Yield (%): 68, m.p (0C): 168-170. IR (KBr, νMax) = 3245, 3118, 2949, 2825, 2775, 2361, 1709, 1651, 1462, 1287, 1225, 1102, 783, 501. 1H-NMR (400MHz, CDCl3): δ 2.206 (s, 6H), 2.316 (s, 3H), 2.337 (s, 3H), 2.446-2.460 (t, J = 5.6Hz, 2H), 4.103-4.117 (t, J = 5.6Hz, 2H), 5.369 (s, 1H), 5.642 (s, 1H), 7.095-7.116 (d, J = 7.6Hz, 2H), 7.199-7.218 (d, J = 7.6Hz, 2H), 7.858 (s, 1H). 13C NMR (CDCl3): δ = 18.845, 21.283, 45.808, 55.536, 57.926, 62.032, 101.434, 126.715, 129.561, 137.800, 141.073, 146.853, 153.675, 165.871. ESI-MS: m/z = 318.67.

DHPM4 2-(dimethylamino)ethyl-6-methyl-4-(4-methoxyphenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-carboxylate: Yield (%): 63, m.p (0C): 158-160. IR (KBr, νMax) = 3248, 3118, 2952, 2829, 2775, 1724, 1653, 1513, 1462, 1228, 1177, 1107, 1034, 841, 785. 1H-NMR (400MHz, CDCl3): δ 2.210 (s, 6H), 2.346 (s, 3H), 2.462-2.477 (t, J = 6.0Hz, 2H), 3.785 (s, 3H), 4.119-4.122 (t, J = 6.0Hz, 2H), 5.364 (s, 1H), 5.498 (s, 1H), 6.826-6.838 (d, J = 4.8Hz, 2H), 7.240-7.252 (d, J = 4.8Hz, 2H), 7.511 (s, 1H). 13C NMR (CDCl3): δ = 13.655,18.195, 45.135, 54.773, 57.228, 59.480, 61.398, 101.003, 113.549, 127.311, 135.609, 145.682, 152.516, 158.801, 165.112. ESI-MS: m/z = 334.69.

DHPM5 2-(dimethylamino)ethyl-6-methyl-4-(4-(dimethylamino)phenyl)-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate: Yield (%): 70, m.p (0C): 194-196. IR (KBr, νMax) = 3245, 3116, 2946, 2823, 2777, 1719, 1651, 1618, 1526, 1456, 1362, 1342, 1231, 1167, 1083, 788. 1H-NMR (400MHz, DMSO-D6): δ 2.110 (s, 6H), 2.225 (s, 3H), 2.379-2.394 (t, J = 6.0Hz, 2H), 2.840 (s, 6H), 4.000-4.015 (t, J = 6.0Hz, 2H), 5.033 (s, 1H), 6.634-6.655 (d, J = 8.4Hz, 2H), 7.035-7.056 (d, J = 8.4Hz, 2H), 7.579 (s, 1H), 9.086 (s, 1H). 13C NMR (DMSO-D6): δ 17.719, 45.260, 53.206, 57.305, 61.059, 99.829, 112.236, 126.887, 132.566, 147.783, 149.771, 152.328, 159.605, 165.426. ESI-MS: m/z = 347.658.

DHPM6 2-(dimethylamino)ethyl-6-methyl-4-(4-(dimethylamino)phenyl)-2-thio-1,2,3,4-tetrahydropyrimidine-5-carboxylate: Yield (%): 48, m.p (0C): 102-104. IR (KBr, νMax) = 3175, 2951, 2857, 2822, 2362, 1685, 1646, 1612, 1579, 1522, 1462, 1347, 1277, 1110, 1035, 949, 814, 777. 1H-NMR (400MHz, DMSO-D6): δ 2.103 (s, 6H), 2.273 (s, 3H), 2.394-2.408 (t, J = 5.6Hz, 2H), 2.866 (s, 6H), 4.033-4.047 (t, J = 5.6Hz, 2H), 5.053 (s, 1H), 6.646-6.668 (d, J = 8.8Hz, 2H), 7.015-7.037 (d, J = 8.8Hz, 2H), 9.577 (s, 1H), 10.220 (s, 1H). 13C NMR (DMSO-d6): δ 15.149, 17.120, 45.253, 53.417, 57.241, 61.380, 64.904, 101.183, 112.216, 127.124, 131.142, 144.504, 149.988, 165.248, 173.912. ESI-MS: m/z = 363.484.

DHPM7 2-(dimethylamino)ethyl-6-methyl-4-(4-chlorophenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-carboxylate: Yield (%): 52, m.p (0C): 142-144. IR (KBr, νMax) = 3243, 3120, 2950, 2777, 1709, 1649, 1463, 1288, 1223, 1086, 979, 788. 1H-NMR (400MHz, CDCl3): δ 2.203 (s, 6H), 2.339 (s, 3H), 2.450-2.465 (t, J = 6.0Hz, 2H), 4.106-4.121 (t, J = 6.0Hz, 2H), 5.386 (s, 1H), 5.989 (s, 1H), 7.274-7.265 (s, 4H), 8.200 (s, 1H). 13C NMR (CDCl3): δ 18.190, 45.073, 54.454, 57.291, 61.285, 100.287, 127.599, 128.372, 133.192, 141.886, 146.682, 153.127, 165.038. ESI-MS: m/z = 338.49.

DHPM8 2-(dimethylamino)ethyl-6-methyl-4-(4-hydroxyphenyl)-2-oxo-1,2,3,4-tetrahydro pyrimidine-5-carboxylate (Table 6.1, entry 8): Yield (%): 50, m.p (0C): 106-108. IR (KBr, νMax) = 3241, 2955, 1696, 1643, 1458, 1228, 1171, 1098, 761, 659. 1H-NMR (400MHz, DMSO-D6): δ 2.114 (s, 6H), 2.294 (s, 3H), 2.400-2.414 (t, J = 5.6Hz, 2H), 4.020-4.034 (t, J = 5.6Hz, 2H), 5.051 (s, 1H), 6.673-6.694 (d, J = 8.4Hz, 2H), 7.036-7.057 (d, J = 8.4Hz, 2H), 7.611 (s, 1H), 9.111 (s, 1H), 9.327 (s, 1H). 13C NMR (DMSO-D6): δ 17.759, 45.180, 53.309, 57.254, 61.014, 99.682, 114.995, 127.416, 135.332, 148.072, 152.261, 156.549, 165.384. ESI-MS: m/z = 320.59.

DHPM9 2-(dimethylamino)ethyl-6-methyl-4-(3-hydroxyphenyl)-2-thio-1,2,3,4-tetrahydro pyrimidine-5-carboxylate: Yield (%): 30, m.p (0C): 110-112. 1H-NMR (400MHz, DMSO-D6): δ 2.095 (s, 6H),

3

2.281 (s, 3H), 2.384-2.413 (t, J = 5.6Hz, 2H), 4.040-4.069 (t, J = 5.6Hz, 2H), 5.084 (s, 1H), 6.633-6.676 (m, 3H), 7.088 (s, 1H), 9.421 (s, 1H), 9.583 (s, 1H), 10.280 (s, 1H). 13C NMR (DMSO-D6): δ 17.272, 45.246, 53.931, 57.232, 61.522, 100.746, 113.349, 114.702, 117.162, 129.593, 144.791, 145.193, 157.519, 165.262, 174.285. ESI-MS: m/z = 335.37.

DHPM10 2-(4-(4-methoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyloxy)-N,N,N-trimethylethanaminium: IR (KBr, νMax): 798, 836, 948, 1098, 1226, 1454, 1638, 1686, 2956, 3107, 3218, 3455. 1H NMR (400MHz, DMSO-D6) δ 2.305 (s, 3H), 2.950 (s, 9H), 3.553–3.589 (m, 2H), 3.722 (s, 3H), 4.378 (s, 2H), 5.107-5.115 (d, 2H), 6.867-6.889 (d, J = 8.8 Hz, 2H), 7.159-7.181 (d, J = 8.8 Hz, 2H), 7.774 (s, 1H), 9.297 (s, 1H). 13C NMR (DMSO-D6): δ 18.039, 30.737, 52.760, 52.977, 55.218, 57.180, 64.037, 98.136, 113.880, 127.629, 136.376, 150.331, 151.953, 158.608, 164.824. ESI-MS: m/z = 348.230.

DHPM11 2-(4-(4-chlorophenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyloxy)-N,N,N-trimethylethanaminium: IR (KBr, νMax): 766, 832, 1072, 1223, 1451, 1637, 1709, 2945, 3093, 3213.1H NMR (400MHz, DMSO-D6) δ 2.309 (s, 1H), 2.966 (s, 9H), 3.561-3.605 (m, 2H), 4.384 (s, 1H), 5.161-5.169 (d, 1H), 7.266-7.287 (d, J = 8.4 Hz, 2H), 7.389-7.410 (d, J = 8.4 Hz, 2H), 7.893 (s, 1H), 9.393 (s,1H). 13C NMR (DMSO-D6): δ 18.057, 29.567, 30.694, 32.086, 52.713, 52.959, 55.793, 57.236, 63.969, 68.529, 97.517, 128.343, 128.495, 131.957, 143.066, 150.813, 151.749, 164.640. ESI-MS: m/z = 352.57.

DHPM12 2-(4-(4-methylphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyloxy)-N,N,N-trimethylethanaminium: IR (KBr, νMax): 752, 888, 951, 1069, 1089, 1232, 1445, 1642, 1698, 3004, 3259, 3392. 1H NMR (400MHz, DMSO-D6) δ 2.264 (s, 3H), 2.303 (s, 3H), 2.940 (s, 9H), 3.559-3.590 (m, 2H), 4.376 (s, 2H), 5.115-5.122 (s, 1H), 7.133 (s, 4H), 7.803 (s, 1H), 9.309 (s, 1H). 13C NMR (DMSO-D6): δ 18.020, 20.670, 29.592, 52.699, 53.276, 57.163, 68.551, 97.944, 126.320, 129.032, 136.644, 141.282, 150.447, 151.944, 164.805. ESI-MS: m/z = 332.27.

DHPM13 2-(4-(4-nitrophenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyloxy)-N,N,N-trimethylethanaminium: IR (KBr, νMax): 756, 863, 950, 1103, 1245, 1349, 1523, 1663, 1696, 3218, 3311.1H NMR (400MHz, DMSO-D6) δ 2.324 (s, 3H), 2.972 (s, 9H), 3.537-3.588 (m, 2H), 4.386 (s, 2H), 5.295-5.303 (s, 2H), 7.527-7.549 (d, J = 8.8 Hz, 2H), 8.014 (s, 1H), 8.205-8.227 (d, J = 8.8 Hz, 2H), 9.491 (s, 1H). 13C NMR (DMSO-D6): δ 18.108, 29.566, 52.709, 53.200, 55.801, 57.339, 63.925, 96.977, 123.882, 127.809, 146.804, 151.268, 151.650, 151.595, 164.528. ESI-MS: m/z = 363.13.

DHPM14 2-(4-(4-ethoxyphenyl)-6-methyl-2-oxo-1,2,3,4-tetrahydropyrimidine-5-carbonyloxy)-N,N,N-trimethylethanaminium: IR (KBr, νMax): 795, 835, 1105, 1233, 1475, 1643, 1702, 2976, 3245, 3413, 3506. 1H NMR (400MHz, DMSO-D6): δ 1.282-1.317 (t, J = 7.2 Hz, 3H), 2.304 (s, 3H), 2.947 (s, 9H), 3.552-3.600 (m, 2H), 3.958-4.010 (q, J = 7.2 Hz, 2H), 4.376 (s, 2H), 5.101-5.109 (d, 1H), 6.849-6.871 (d, J = 8.8 Hz, 2H), 7.143-7.164 (d, J = 8.8 Hz, 2H), 7.768 (s, 1H), 9.290 (s, 1H). 13C NMR (DMSO-D6): δ 15.115, 18.469, 30.068, 32.581, 53.114, 53.396, 56.298, 57.638, 63.500, 64.428, 68.980, 96.480, 114.757, 128.058, 136.688, 150.815, 152.388, 158.293, 165.256, 208.854. ESI-MS: m/z = 362.28.

4

1H NMR spectra of DHPMs

DHPM 1

DHPM 2

DHPM3

5

DHPM4

DHPM5

DHPM6

6

DHPM7

DHPM8

7

DHPM9

DHPM10

DHPM11

8

DHPM12

9

DHPM13

DHPM14

10

13C NMR spectra of DHPMs

DHPM 1

DHPM 2

11

DHPM3

DHPM4

DHPM5

12

DHPM6

DHPM7

DHPM8

13

DHPM9

DHPM10

DHPM11

14

DHPM12

15

DHPM13

DHPM14

16

17