K. M. Khan et al. / Bioorg. Med. Chem. 11 (2003) 1381–1387
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C7H8N2O2: C, 55.26; H, 5.30; N, 18.41. Found: C,
55.19; H, 5.37; N, 18.34.
127.7 (C-2), 128.5 (C-4), 136.6 (C-6), 171.3 (CO); IR
(KBr) nmax 3323, 1629, 1566, 1491, 1273, 865, 619 cmꢀ1
;
UV (methanol) lmax (log e) 274 (4.87); MS (m/z) 150
(M+, 54), 119 (100), 91 (70), 77 (52), 63 (44). Anal.
calcd for C8H10N2O: C, 63.98; H, 6.71; N, 18.65.
Found: C, 63.89; H, 6.80; N, 18.56.
2-Methoxybenzohydrazide (2l). Yield 12 g (90%); Rf
0.50 (hexane/ethyl acetate, 5:5); 1H NMR (500 MHz,
CDCl3) l 3.86 (s, 3H, OCH3), 4.29 (br, 2H, NH2), 6.89
(dd, 1H, J=8.3, 1.9 Hz, H-5), 7.00 (dt, 1H, J=8.3, 1.9
Hz, H-4), 7.36 (dt, 1H, J=8.3, 1.9 Hz, H-3), 8.11 (dd,
1H, J=8.3, J=1.9 Hz, H-2), 9.43 (br, s, 1H, CONH);
13C NMR (125 MHz, CDCl3) 56.2 (CH3) 113.1 (C-5),
119.8 (C-4), 122.3 (C-3), 125.2 (C-2), 135.4 (C-1), 156.9
(C-6), 168.9 (CO); IR (KBr) nmax 3331, 3008, 1633,
General procedure for the preparation of (2i)and ( 2j).
Hydrazine hydrate (236 mmol) was added to methyl 2-
naphthoate (59 mmol)/methyl 2-phenylacetate (59
mmol). After refluxing for 5 h the solid obtained was
washed with hexane to afford 2i and 2j respectively.
1578, 1499, 1321, 1277, 765, 608 cmꢀ1; UV (C HOH)
3
lmax (log e) 207 (2.8); MS (m/z) 166 (M+, 26), 152 (19),
135 (100), 121 (59), 105 (5), 77 (55), 65 (18), 51 (10).
Anal. calcd for C8H10N2O2: C, 57.82; H, 6.07; N, 16.86.
Found: C, 57.73; H, 6.16; N, 16.77.
2-Naphthoylhydrazine (2i). Yield 15 g (71%); mp 152 ꢁC;
Rf 0.54 (methanol/ethyl acetate, 1:9); 1H NMR
(400 MHz, DMSO-d6) d 4.54 (br, s, 2H, NH2), 8.41–7.61
(m, 7H, Ar-H), 9.89 (bs, 1H, CONH); 13CNMR
(75 MHz, DMSO-d6) 123.9 (C-5), 126.6 (C-8), 127.2 (C-
4), 127.4 (C-3), 127.5 (C-1), 127.8 (C-7), 128.7 (C-6),
130.7 (C-2), 132.2 (C-10), 134.1 (C-9), 166.0 (CO); IR
(KBr) nmax 3308, 3210, 3048, 1622, 1558, 1505 cmꢀ1; UV
(methanol) lmax (log e) 280 (4.97); MS (m/z) 186 (M+,
40), 155 (100), 127 (46), 77 (5). Anal. calcd for
C11H10N2O: C, 70.95; H, 5.41; N, 15.04. Found: C,
70.87; H, 5.49; N, 14.96.
Benzohydrazide (2m). Yield 11 g (79%); Rf=0.45 (hex-
1
ane/ethyl acetate, 3:7); H NMR (500 MHz, CDCl3) d
4.52 (br. s, 2H, NH2), 7.56–7.01 (m, 5H, Ar-H), 10.01
(br. s, 1H, CONH); 13C NMR (125 MHz, CDCl3) 127.3
(C-3/C-5), 128.6 (C-2/C-6), 131.2 (C-4), 134.2 (C-1),
169.8 (CO); IR (KBr) nmax 3325, 1614, 1571, 1491, 1329,
833, 666, 516 cmꢀ1; UV (methanol) lmax (log e) 201
(3.9; MS (m/z) 136 (M+, 8), 105 (78), 77 (100), 51 (62).
Anal. calcd for C7H8N2O: C, 61.75; H, 5.92; N, 20.58.
Found: C, 61.66; H, 6.01; N, 20.49.
Phenyl acetyl hydrazine (2j). Yield 18 g (49%); Rf=0.45
(methanol/ethyl acetate, 1:9); 1H NMR (300 MHz,
CD3OD) d 3.45 (s, 2H, PhCH2CO), 4.26 (br, s, 2H,
NH2), 7.19–7.29 (m, 5H, Ar-H), 9.51 (br, s, 1H,
CONH); 13CNMR (75 MHz, CD 3OD) 41.8 (PhCH2),
127.4 (C-3/C-5), 128.9 (C-4), 129.3 (C-2/C-6), 130.3 (C-
1), 171.6 (CO); IR (KBr) nmax 3305, 3023, 1643, 1534,
1358 cmꢀ1; UV (methanol) lmax (log e) 205 (3.98); MS
(m/z) 149.8 (M+, 56), 117 (66), 91 (100), 65 (22). Anal.
calcd for C8H10N2O: C, 63.98; H, 6.71; N, 18.65.
Found: C, 63.91; H, 6.78; N, 18.58.
4-Methylbenzohydrazide (2q). Yield 13
g
(74%);
1
Rf=0.48 (ethyl acetate); H NMR (300 MHz, CD3OD)
d 2.36 (s, 3H, CH3), 4.48 (br, s, 2H, NH2), 7.19 (d, 2H,
J=8.3 Hz, H-3/H-5), 7.63 (d, 2H, J=8.3 Hz, H-2/H-6),
9.54 (bs, 1H, CONH). 13CNMR (75 MHz, CD 3OD) d
21.7 (CH3), 126.8 (C-2/C-6), 129.6 (C-3/C-5), 136.4 (C-
4), 170.1 (CO). IR (KBr) nmax 3319, 3189, 1627, 1563,
1489, 1276, 855, 611 cmꢀ1; UV (methanol) lmax (log e)
197.4 (4.73); MS (m/z) 150 (M+, 67), 135 (30), 119 (99),
91 (100), 77 (10), 63 (36), 49 (1). Anal. calcd for
C8H10N2O: C, 63.98; H, 6.71; N, 18.65. Found: C,
63.91; H, 6.78; N, 18.58.
General procedure for the preparation of (2k) , 2(n–2p),
(2r)and ( 2u). Hydrazine hydrate (133 mmol) was added
to ethyl acetate (102 mmol)/methyl butyrate (102
mmol)/ methyl propionate (102 mmol)/ methyl
2-methylpropanoate (102 mmol)/ methyl hexanoate
(102 mmol) or methyl nonanoate (102 mmol). After
refluxing for 5 h the solid obtained was washed with
hexane to afford (2k), (2n–2p), (2r) and 2u) respectively.
Nicotinohydrazide (2s). Yield 9 g (99%); Rf=0.50 (ethyl
1
acetate/methanol, 9:1); H NMR (300 MHz, DMSO-d6)
d 4.47 (br, s, 2H, NH2), 7.54 (dt, 1H, J=7.9, 2.1 Hz, H-
5), 8.24 (t, 1H, J=7.9 Hz, H-4), 8.71 (dt, 1H, J=7.9, 2.1
Hz, J=2.1 Hz, H-6), 8.98 (t, 1H, J=2.1 Hz, H-2), 9.54
(br. s, 1H, CONH); 13CNMR (75 MHz, DMSO- d6) d
125.4 (C-3), 132.4 (C-5), 135.2 (C-4), 149.1 (C-6), 151.1
(C-2), 169.3 (CO); IR (KBr) nmax 3323, 3178, 1639,
1565, 1483, 1285, 833, 629 cmꢀ1; UV (methanol) lmax
(log e) 198 (4.7) MS (m/z) 137 (M+, 86), 122 (25), 106
(100), 78 (100), 51 (54). Anal. calcd for C6H7N3O: C,
52.55; H, 5.14; N, 30.64. Found: C, 52.46; H, 5.23; N,
30.55.
Acetohydrazide (2k). Yield 8 g (97%); Rf=0.45 (hexane/
ethyl acetate, 1:9); 1H NMR (400 MHz, CD3OD) d 1.90
(s, 3H, CH3); 13CNMR (100 MHz, CD 3OD) d 18.51
(CH3), 172.53 (CO); IR (KBr) nmax 3479, 2953, 1653,
1283, 944, 699, 614 cmꢀ1; UV (methanol) lmax (log e)
202 (3.3); MS (m/z) 74 (M+, 100), 56 (86). Anal. calcd
for C2H6N2O: C, 32.43; H, 8.16, N, 37.81. Found: C,
32.37, H, 8.23, N, 37.88.
2-Methylbenzohydrazide (2t). Yield 14 g (71%); Rf 0.54
(ethyl acetate/methanol, 9:1); 1H NMR (300 MHz,
DMSO-d6) d 2.28 (s, 3H, CH3), 4.21 (br, s, 2H, NH2),
7.03 (dd, 1H, J=8.1, 1.7 Hz, H-5), 7.10 (dt, 1H, J=8.1,
1.7 Hz, H-3), 7.25 (dt, 1H, J=8.1, 1.7 Hz, H-4), 7.71
(dd, 1H, J=8.1, 1.7 Hz, H-2), 10.01 (bs, 1H, CONH);
13CNMR (75 MHz, DMSO- d6) 19.5 (CH3), 125.6 (C-3),
Butanohydrazide (2n). Yield 12 g (89%); Rf=0.55 (hex-
ane/ethyl acetate, 2:8); 1H NMR (300 MHz, D2O) d 2.08
(t, 2H, J=7.5 Hz, H-2), 1.50 (m, 2H, H-3), 0.81 (t, 3H,
J=6.5 Hz, CH3); 13CNMR (75 MHz, D 2O) d 177.1
(CO), 36.1 (C-2), 16.9 (C-3), 13.8 (CH3); UV (methanol)
lmax (log e) 195 (2.97); IR (KBr) nmax 3254, 2961, 1681,
1266, 965, 799, 633 cmꢀ1; MS (m/z) 102 (M+, 38),