938
SHABLYKIN et al.
Table 2. 1H NMR and IR spectra of compounds II VII
Comp. no.
1H NMR spectrum, , ppm (DMCO-d6)
2.27 s (3H, CH3), 2.59 s (3H, CH3), 6.24 s (1H, 4-H, pyrazole), 7.58 m (3H, Harom), 7.96 m (2H, Harom
2.20 s (3H, CH3), 2.21 s (3H, CH3), 6.13 s (1H, 4-H, pyrazole), 7.62 m (3H, Harom), 8.08 m (2H, Harom),
9.56 br.s, 10.02 br.s (2H, NH2)
IIa
)
IIIb
IV
2.22 s (3H, CH3), 2.23 s (3H, CH3), 3.20 br.s (1H, NH), 6.18 s (1H, 4-H, pyrazole), 7.61 m (3H, Harom),
8.10 m (2H, Harom
)
Vc
2.20 s (6H, 2CH3), 5.63 br.s (2H, NH2), 6.05 s (1H, 4-H, pyrazole), 7.55 m (3H, Harom), 8.04 m (2H, Harom),
9.78 br.s (1H, OH)
VIa
VIb
VIc
VII
2.27 s (6H, CH3), 6.22 s (1H, 4-H, pyrazole), 7.40 m (3H, Harom), 7.61 m (3H, Harom), 7.81 m (2H, Harom),
8.13 m (2H, Harom), 8.16 s (1H, 5-H, thiazole)
2.25 s (6H, CH3), 2.33 s (3H, CH3), 6.28 s (1H, 4-H, pyrazole), 7.24 m (2H, Harom), 7.63 m (3H, Harom),
7.73 m (2H, Harom), 8.80 m (2H, Harom), 8.20 s (1H, 5-H, thiazole)
2.27 s (6H, CH3), 6.20 s (1H, 4-H, pyrazole), 7.57 m (5H, Harom), 7.75 d (2H, Harom), 8.11 m (2H, Harom),
8.22 s (1H, 5-H, thiazole)
2.18 s (3H, CH3), 2.23 s (3H, CH3), 2.62 s (3H, CH3), 6.13 s (1H, 4-H, pyrazole), 7.60 m (3H, Harom),
8.07 m (2H, Harom
)
a
1
b
1
c
1
IR spectrum, , cm : 2250 (C N). IR spectrum, , cm : 3280, 3370 (NH ). IR spectrum, , cm : 3350, 3450 (NH , OH).
2
2
hydrogen sulfide at 20 25 C; the mixture was left to
stand for 12 h at 20 25 C and diluted with 50 ml of
water, and the precipitate was filtered off, washed
water, and purified by recrystallization.
and 0.015 mol of sodium hydrogen carbonate. When
the evolution of gaseous CO2 ceased, 20 ml of ethanol
was added, the mixture was heated for 2 h under re-
flux and cooled, the solvent was evaporated to dryness
under reduced pressure, and the residue was thorough-
ly washed with water, dried in a vacuum desiccator
over phosphoric anhydride, and purified by recrystal-
lization.
b. A suspension of 0.02 mol of compound II in
20 ml of DMF was saturated with gaseous hydrogen
chloride over a period of 1 h, 0.04 mol of thioacet-
amide was added, and the mixture was heated for
0.5 h on a water bath. The solvent was removed under
reduced pressure, the residue was treated with 100 ml
of a 5% aqueous solution of sodium hydrogen car-
bonate, and the precipitate was filtered off and puri-
fied by recrystallization. Yield 95% (after recrystal-
lization from ethanol). Samples of compound III
prepared according to methods a and b showed no
depression of the melting point on mixing, and their
4-(4-Aryl-1,3-thiazol-2-yl)-5-(3,5-dimethyl-1H-
pyrazol-1-yl)-2-phenyl-1,3-oxazoles VIa VIc (ge-
neral procedure). Compound III, 0.01 mol, was dis-
persed in 70 ml of methanol, 0.01 mol of the corre-
sponding substituted bromoacetophenone was added,
and the mixture was heated for 6 under reflux. After
cooling, the precipitate was filtered off, washed with
10 ml of a 5% aqueous solution of sodium hydrogen
carbonate and 20 ml of water, and purified by re-
crystallization from ethanol.
1
IR and H NMR spectra were identical.
5-[5-(3,5-Dimethyl-1H-pyrazol-1-yl)-2-phenyl-
1,3-oxazol-4-yl]-1H-tetrazole (IV). Sodium azide,
0.0045 mol, and ammonium chloride, 0.0045 mol,
were added to a solution of 0.004 mol of compound II
in 10 ml of DMF, and the mixture was heated for 6 h
at 100 C, poured into 70 ml of water, and acidified
with hydrochloric acid to pH 6 7. The precipitate
was filtered off, dried in a vacuum desiccator over
phosphoric anhydride, and purified by crystallization.
3-[5-(3,5-Dimethyl-1H-pyrazol-1-yl)-2-phenyl-
1,3-oxazol-4-yl]-5-methyl-1,2,4-oxadiazole (VII).
Amidoxime V, 0.03 mol, was dissolved in 10 ml of
benzene, 5 ml of pyridine was added, the mixture was
cooled to 5 10 C, and a solution of 0.033 mol of
acetyl chloride in 5 ml of anhydrous benzene was
added over a period of 10 min. The mixture was left
to stand for 12 h at 20 25 C, volatile substances were
removed under reduced pressure, and the precipitate
was thoroughly washed with water, dried in a vacuum
desiccator over phosphoric anhydride, and purified by
recrystallization from ethanol.
5-(3,5-Dimethyl-1H-pyrazol-1-yl)-N -hydroxy-2-
phenyl-1,3-oxazole-4-carboximidamide (V). Water,
2 ml, was added to a mixture of 0.0075 mol of com-
pound II, 0.015 mol of hydroxylamine hydrochloride,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 77 No. 5 2007