Download (6Mb) - Etheses - Saurashtra University

More documents

Recommendations

Info

Chapter 4 Synthesis of highly substituted pyrazolopyrimidine Synthesis of 5-amino-N-cyclohexyl-3-(methylthio)-1H-pyrazole-4- carboxamide (5). A 100mL conical flask equipped with magnetic stirrer and septum was charged 2-cyano-N-cyclohexyl-3,3-bis(methylthio)acrylamide (4) (0.1mol) in isopropyl alcohol (100 mL) and hydrazine hydrate (0.1mol). The Reaction mixture was heated to reflux for 2 h. After completion of the reaction, it was poured into 50mL cold water. The precipitated crude product was purified by filtration followed by crystallization from EtOH. General synthesis of Acetoacetanilide derivatives (AAA) (8a-x). A mixture containing the primary amine (7a-h) (10 mmol), β-keto esters (6ac) (10 mmol), and catalytic amount of sodium or potassium hydroxide (10 %) in toluene (50 mL) was refluxed at 110 o C for 12-15 h. The reaction was monitored by TLC. After completion of reaction, the solvent was removed under vaccuo and the residue was crystallized from methanol. General synthesis of ketene dithioacetals (9a-x). A 100mL conical flask equipped with magnetic stirrer and septum was charged with a solution of acetoacetanilide derivatives (8a-x) (10 mmol) in DMF (10 mL). Dry K 2 CO 3 (20 mmol) was added and the mixture was stirred for 2 h at room temperature. CS 2 (10 mmol) was then added and the mixture was stirred for an additional 2 h at room temperature. Methyl iodide (20 mmol) was added at 0-5 o C and the mixture was stirred for 4 h at room temperature. The reaction was monitored by TLC. After completion, reaction mixture poured into water (50 mL). The precipitated crude product was purified by filtration followed by crystallization from EtOH. General synthesis of substituted and fused pyrazolopyrimidines (10a-x). A mixture of 5-amino-N-cyclohexyl-3-(methylthio)-1H-pyrazole-4- carboxamide (5) (3.0mmol), potassium carbonate (6.0mmol) and ketene dithioacetals (9a-x) (3.0mmol) in isopropyl alcohol (10 mL) was heated to reflux for 7-10 h. The progress of reaction mixture was monitored by TLC. After completion of reaction, the mixture was cooled to room temperature and solid residue was filtered and washed with 10mL of isopropyl alcohol followed by 50 ml of water. The product was crystallized from MeOH to give 10a-x in 87-97% yield. Department of Chemistry, <strong>Saurashtra</strong> university, Rajkot-360005 140
Chapter 4 Synthesis of highly substituted pyrazolopyrimidine Spectral data of newly synthesized compounds 2-(bis(methylthio) methylene)-4-methyl-3-oxo-N-p-tolylpentanamide 9i. yellow solid; mp 155-158 ° C; R f 0.54 (8:2 hexane-EtOAc); IR (KBr): 3373, 3072, 2895, 2828, 1694, 1635, 1482, 1343, 1298 cm -1 ; 1 H NMR (400 MHz, DMSO): δ 1.18-1.20 (m, 6H, 2 × i prCH 3 ), 1.57 (s, 3H, CH 3 ), 2.44 (s, 6H, 2 × SCH 3 ), 3.17-3.24 (m, 1H, i prCH), 6.99–7.54 (m, 4H, Ar), 8.38 (br, s, 1H, -CONH); MS (m/z):323 [M + ];Anal. Calcd for C 16 H 21 NO 2 S 2 : C, 59.41; H, 6.54; N, 4.33; Found: C, 59.33; H, 6.45; N, 4.23. 2-(bis(methylthio)methylene)-N-(4-methoxyphenyl)-4-methyl-3-oxopentanamide 9o. yellow solid; mp 169-171 ° C; R f 0.57 (8:2 hexane-EtOAc); IR (KBr): 3439, 3007, 2928, 2808, 1599, 1462, 1327, 1255 cm -1 ; 1 H NMR (400 MHz, DMSO): δ 1.18-1.20 (m, 6H, 2 × i prCH 3 ), 2.44 (s, 6H, 2 × SCH 3 ), 3.17-3.24 (m, 1H, i prCH), 3.75 (s, 3H, OCH 3 ), 6.99–7.54 (m, 4H, Ar), 8.38 (br, s, 1H, -CONH); MS (m/z):339 [M + ];Anal. Calcd for C 16 H 21 NO 3 S 2 : C, 56.61; H, 6.24; N, 4.13; Found: C, 56.53; H, 6.14; N, 4.06. N-(4-chlorophenyl)-2-(cyclopropylcarbonyl)-3,3-bis(methylsulfanyl)prop-2- enamide 9t. Yello solid; mp 138-140 ° C, R f 0.52 (8:2 hexane-EtOAc); IR (KBr): 3364, 2927, 1674, 1533, 1462, 1281, 1112, 873 cm -1 ; 1 H NMR (300 MHz, CDCl 3 ): δ 1.02- 1.06 (m, 2H, CH 2 ), 1.21-1.24 (m, 2H, CH 2 ), 2.37-2.43 (m, 1H, CH), 2.47 (s, 6H, 2x SCH 3 ), 7.26-7.29 (d, 2H, j=9.6Hz, Ar-H), 7.53-7.55 (d, 2H, j=8.7Hz, Ar-H), 8.69 (s, 1H, NH); MS (m/z): 342 (M + ); Anal. Calcd for C 15 H 16 ClNO 2 S 2 : C, 52.70; H, 4.72; N, 4.10; Found: C, 52.72; H, 4.75; N, 4.12. 2-(Cyclopropylcarbonyl)-N-(4-methoxyphenyl)-3,3-bis(methylsulfanyl)prop-2- enamide 9w. Yello solid; mp 154-156 ° C, R f 0.61 (8:2 hexane-EtOAc); IR (KBr): 3354, 2925, 1684, 1525, 1450, 1285, 1112, 880, 753 cm -1 ; 1 H NMR (300 MHz, CDCl 3 ): δ 1.02-1.04 (m, 2H, CH 2 ), 1.22 (m, 2H, CH 2 ), 2.39-2.42 (m, 1H, CH), 2.47 (s, 6H, 2x SCH 3 ), 3.84 (s, 3H, OCH 3 ), 6.85-6.88 (d, 2H, j=8.7Hz, Ar-H), 7.48-7.51 (d, 2H, j=8.7Hz, Ar-H), 8.35 (s, 1H, NH); MS (m/z): 337 (M + ); Anal. Calcd for C 16 H 19 NO 3 S 2 : C, 56.95; H, 5.68; N, 4.15; Found: C, 56.92; H, 5.65; N, 4.12. N 3 -cyclohexyl-7-methyl-2,5-bis(methylthio)-N 6 -p-tolylpyrazolo[1,5-a]pyrimidine- 3,6-dicarboxamide 10a. White solid; mp >320 o C, R f 0.31 (9:1Chloroform: Methanol); IR (KBr): 3309, 3254, 3016, 2925, 1671, 1473, 831, 807, 758 cm -1 ; Department of Chemistry, <strong>Saurashtra</strong> university, Rajkot-360005 141
Page 1 and 2:
Saurashtra University Re - Accredit
Page 3 and 4:
Statement under O.Ph.D.7 of Saurash
Page 5 and 6:
Wxw|vtàxw àÉ `ç YtÅ|Äç
Page 7 and 8:
I am thankful to FIST/DST and SAP/U
Page 9 and 10:
Chapter 4 Synthesis and Characteriz
Page 11 and 12:
Chapter - 1 Palladium Catalyzed Syn
Page 13 and 14:
Chapter 1 Synthesis of functionaliz
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Chapter - 2 Synthesis and Biologica
Page 57 and 58:
Chapter 2 Synthesis of substituted
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Chapter 3 Synthesis of trisubstitut
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104: Chapter 3 Synthesis of trisubstitut
Page 135 and 136: Chapter 4 Synthesis of highly subst
Page 153: Chapter 4 Synthesis of highly subst
Page 173 and 174: Chapter-5 Synthesis of highly subst
Page 205 and 206:
Chapter-5 Synthesis of highly subst
Page 207 and 208:
Page 209 and 210:
Page 211 and 212:
Page 213 and 214:
Page 215 and 216:
Page 217 and 218:
Chapter 6 Synthesis of benzodiazepi
Page 219 and 220:
Page 221 and 222:
Page 223 and 224:
Page 225 and 226:
Page 227 and 228:
Page 229 and 230:
Page 231 and 232:
Page 233 and 234:
Page 235 and 236:
Page 237 and 238:
Page 239 and 240:
Page 241 and 242:
Page 243 and 244:
Page 245 and 246:
Page 247 and 248:
Page 249 and 250:
Page 251 and 252:
pyrazole derivative were faster and
Page 253:
Conferences participated 1. “15 t
show all

Download (6Mb) - Etheses - Saurashtra University

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?