Y. Huang et al. / Bioorg. Med. Chem. 7 (1999) 607±619
617
31.80, 25.91, 23.42, 22.40, 21.98, 17.91; MS (FAB) 563.1
(16) (MH+).
1H NMR (360 MHz, CD2Cl2) (conformer A) d 8.33±
8.20 (m, 3H, N-NH, ArH), 7.80 (ddd, 1H, J=7.7, 7.1,
1.3 Hz, ArH), 7.38±7.28 (m, 1H, ArH), 6.41 (d, 1H,
J=6.5 Hz, CONH), 5.15±5.05 (m, 1H, CH), 3.88±3.77
(m, 2H, NCH2), 2.95 (s, 3H, NCH3), 2.92 (s, 3H,
NCH3), 2.75±2.67 (m, 2H, CH2CO), 1.88 (s, 3H,
COCH3), 1.17 (d, 3H, J=6.8 Hz, CH3 Ala); (conformer
B) d 8.33±8.20 (m, 3H, N-NH, ArH), 7.69 (ddd, 1H,
J=7.7, 7.1, 1.3 Hz, ArH), 7.38±7.28 (m, 1H ArH), 6.58
(d, 1H, J=6.5 Hz, CONH), 4.97±4.87 (m, 1H, CH),
3.88±3.77 (m, 2H, NCH2), 2.88 (s, 3H, NCH3), 2.85 (s,
3H, NCH3), 2.82±2.74 (m, 2H, CH2CO), 1.95 (s, 3H,
COCH3), 1.30 (d, 3H, J=6.8 Hz, CH3 Ala); 13C NMR
(75 MHz, CD3OD) (conformer A) d 174.40, 172.29,
169.37, 143.05, 141.31, 134.74, 126.51, 125.96, 125.82,
45.94, 45.79, 37.54, 35.59, 32.43, 23.18, 18.69; (con-
former B) d 173.09, 170.63, 169.58, 142.54, 141.31,
134.50, 125.92, 125.82, 125.46, 45.66, 45.19, 37.15,
35.29, 31.70, 23.18, 18.69; MS (FAB) 398.0 (21) (MH+).
Anal. calcd for C16H23N5O5S: C, 48.35; H, 5.83; N,
17.62. Found: C, 48.11; H, 5.56; N, 17.32.
3-[N1-(Acetyl-L-leucyl-L-alanyl-ꢀ-alanyl)-N2-(benzyloxy-
carbonyl)hydrazino]-N,N-(dimethyl)propanamide
(24).
The above procedure for the preparation of 19, was
adapted to convert 22 (0.130 g, 0.3 mmol) and Ac-Leu-
Ala-OH (73.2 mg, 0.3 mmol) to the crude product. This
was puri®ed by HPLC (linear gradient elution over
20 min of acetonitrile and water, from 20% to 40%, tR
14.2 min) to give 24 (0.110 g, 65%) as a white solid: mp
156±158 ꢁC; IR (CH2Cl2 cast) 3289, 2956, 2934, 1738,
1644, 1538, 1451, 1412, 1243 cm 1; 1H NMR (300 MHz,
CD2Cl2) d 8.85±8.50 (brs, 1H, N-NH), 7.43±7.30 (m,
5H, ArH), 7.30±7.15 (brs, 1H, CONH), 7.15±7.00 (s,
1H, CONH), 6.85±6.50 (brs, 1H, CONH), 5.16 (s, 2H,
CH2O), 4.55±4.30 (m, 2H, 2 CH), 4.30±4.00 (s, 1H,
NCHBH), 3.60±3.20 (m, 3H, NCHAH, NCH2), 2.93 (s,
3H, NCH3), 2.86 (s, 3H, NCH3), 2.86±2.00 (m, 4 H, 2
CH2CO), 1.95 (s, 3H, CH3), 1.75±1.40 (m, 3H, CH and
CH2), 1.35±1.25 (d, 3H, J=7.0 Hz, CH3), 0.91 (d, 3H,
J=6.3 Hz, CH3), 0.89 (d, 3H, J=6.3 Hz, CH3); 13C
NMR (75 MHz, CD2Cl2) d 174.25, 172.72, 172.40,
172.00, 170.80, 156.66, 136.33, 128.95, 128.71, 128.43,
68.03, 52.47, 49.40, 45.64, 41.67, 37.47, 35.69, 35.49,
32.31, 31.86, 25.16, 23.18, 23.14, 22.06, 18.5 1; MS
(FAB) 563.2 (38) (MH+).
3-[N1-(Acetyl-L-alanyl)-N2-(o-nitrophenylsulfenyl)hydra-
zino]-N,N-(dimethyl)propanamide (26). The above
procedure for the preparation of 25 was used with Cbz-
hydrazino derivative 20 (0.378 g, 1 mmol) to give the
intermediate 3-[N1-(acetyl-lL-alanyl)hydrazino]-N,N-
(dimethyl)propanamide (0.243 g, quantitative) as a col-
orless oil: IR (CH2Cl2 cast) 3312, 3213, 2933, 1633,
1541 cm 1; 1H NMR (300 MHz, CD3OD) d 5.24 (q, 1H,
J=7.0 Hz, CH), 3.80±3.60 (m, 2H, NCH2), 3.04 (s, 3H,
NCH3), 2.91 (s, 3H, NCH3), 2.72 (t, 2H, J=6.9 Hz,
CH2CO), 1.94 (s, 3H, CH3), 1.27 (d, 3H, J=7.0 Hz,
CH3); 13C NMR (75 MHz, CD3OD) d 176.59, 173.55,
172.69, 48.15, 47.18, 37.74, 35.67, 31.74, 22.43, 17.54;
MS (FAB) 245.2 (100) (MH+).
3-[N1-(Acetyl-D-alanyl)-N2-(o-nitrophenylsulfenyl)hydra-
zino]-N,N-(dimethyl)propanamide (25). To a solution of
Cbz-hydrazino derivative 19 (0.378 g, 1 mmol) in
methanol (20 mL) under argon was added 10% palla-
dium on charcoal catalyst (38 mg). The mixture was
stirred under an atmosphere of hydrogen until absorp-
tion of gas ceased. The catalyst was removed by ®ltra-
tion through a column of Celite and the ®ltrate was
concentrated in vacuo to give 3-[N0-(acetyl-d-alanyl)-
hydrazinol-N,N-(dimethyl)propanamide (0.244 g, quan-
titative) as a colorless oil: IR (CH2Cl2 cast) 3314, 3214,
This compound (0.100 g, 0.41 mmol), o-nitrophenyl-
sulfenyl chloride (77.7 mg, 0.41 mmol) and triethylamine
(57.2 mL, 0.41 mmol) were reacted as above to give the
crude product. This was puri®ed by HPLC (linear gra-
dient elution over 20 min of acetonitrile and water, from
25% to 45%, tR 10.1 min) to give the title compound 26
(0.120 g, 74%) as a yellow powder. Spectral character-
ization indicated a mixture of conformers (conformer
A:conformer B, 2:1): mp 58±70 ꢁC (dec); IR (CH2Cl2
cast) 3284, 3209, 2934, 1642, 1592, 1565, 1510, 1337,
1
2934, 1636, 1542 cm 1; H NMR (360 MHz, CD3OD) d
5.24 (q, 1H, J=7.0 Hz, CH), 3.86±3.60 (m, 2H, NCH2),
3.04 (s, 3H, NCH3), 2.91 (s, 3H, NCH3), 2.72 (t, 2H,
J=6.9 Hz, CH2CO), 1.95 (s, 3H, CH3), 1.27 (d, 3H,
J=7.0 Hz, CH3); 13C NMR (75 MHz, CD3OD) d
176.60, 173.55, 172.70, 48.38, 47.18, 37.73, 35.67, 31.74,
22.42, 17.54; MS (FAB) 245.3 (100) (MH+). Anal. calcd
for C10H20N4O3: C, 49.17; H, 8.25; N, 22.93. Found: C,
48.86; H, 8.52; N, 22.62.
1
735 cm 1; H NMR (300 MHz, CD2Cl2) (conformer A)
d 8.34±8.20 (m, 3H, N-NH, ArH), 7.78 (ddd, 1H,
J=7.7, 7.2, 1.3 Hz, ArH), 7.40±7.28 (m, 1H, ArH), 6.34
(d, 1H, J=7.30 Hz, CONH), 5.15±5.00 (m, 1H, CH),
3.90±3.77 (m, 2H, NCH2), 2.95 (s, 3H, NCH3), 2.92 (s,
3H, NCH3), 2.71 (t, 2H, J=5.5 Hz, CH2CO), 1.88 (s,
3H, COCH3), 1.16 (d, 3H, J=6.8 Hz, CH3); (conformer
B) d 8.34±8.20 (m, 3H, N-NH, ArH), 7.69 (ddd, 1H,
J=7.7, 7.2, 1.3 Hz, ArH), 7.40±7.28 (m, 1H, ArH), 6.48
(d, 1H, J=7.10 Hz, CONH), 4.98±4.85 (m, 1H, CH),
3.90±3.77 (m, 2H, NCH2), 2.88 (s, 3H, NCH3), 2.86 (s,
3H, NCH3), 2.80 (t, 2H, J=5.5 Hz, CH2CO), 1.95 (s, 3H,
COCH3), 1.30 (d, 3H, J=6.8 Hz, CH3); 13C NMR
(75 MHz, CD3OD) (conformer A) d 174.36, 172.33,
169.40, 143.05, 141.28, 134.75, 126.51, 125.97, 125.83,
45.94, 45.84, 37.57, 35.61, 32.46, 23.20, 18.69; (conformer
To a stirred solution of this intermediate (81.1 mg,
0.33 mmol) and o-nitrophenylsulfenyl chloride (62.9 mg,
0.33 mmol) in DMF (2 mL) under argon, at 10 ꢁC, was
added triethylamine (50 mL, 0.33 mmol). After 30 min at
10 ꢁC, the reaction mixture was allowed to warm to
room temperature, and was then stirred for 1 h. The
solution was concentrated in vacuo. Puri®cation by
HPLC (linear gradient elution over 20 min of acetoni-
trile and water, from 25% to 45%, ¯ow rate 15.0 mL
min 1, tR 11.6 min) gave the title compound 25 (0.108 g,
82%) as a yellow powder. Spectral characterization
indicated a mixture of conformers (conformer A:con-
former B, 2:1): mp 52±63 ꢁC (dec); IR (CH2Cl2 cast)
1
3283, 3209, 2934, 1641, 1592, 1565, 1510, 1337, 735 cm
;