الفهرس 
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Abstract
The 1H NMR spectrum (DMSO-d6, 500 MHz) of carbohydrazone 322 showed the
(NH) proton as a singlet at δ 11.89 ppm (D2O exchangeable), followed by two singlets at δ
9.40 and 8.56 ppm for the proton at position-3 in quinoxaline moiety and the aldimino proton
(CH=N), respectively, then a triplet at δ 8.08 ppm (J = 8.4 Hz) for H-5 and H-8 then a
multiplet at δ 7.83-7.87 ppm for H-6 and H-7. The proton at positison-4 in the furan ring
appeared as a singlet at δ 6.84 ppm. The sugar region showed the 1’-OH as a doublet at δ 5.22
ppm (J1’,OH = 6.85 Hz) and the other hydroxyl signals 2’-OH and 3’-OH appeared as two
doublets at δ 4.64 and 4.53 ppm (J2’,OH = 5.35 Hz and J3’,OH = 6.1 Hz) respectively, and 4’-OH
as a triplet at δ 4.38 ppm (J4’,OH = 6.1 Hz). After deuteration the protons of hydroxyl groups
disappeared and H-1’ was shown as a doublet at δ 4.80 ppm (J1’,2’ = 6.1 Hz), H-2’, H-3’ as a
multiplet at δ 3.54-3.61 ppm, H-4’b as a multiplet at 3.50-3.53 ppm and H-4’a as a doublet of
doublet δ 3.39-3.42 ppm (J3’,4’a = 6.5 Hz and J4’a,4’b = 11.5 Hz). The methyl protons at
position-2 in the furan ring appeared as a singlet at 2.53 ppm. While the 1H NMR spectrum
(DMSO-d6, 500 MHz) of the major isomer of carbohydrazone 323 showed two singlet bands
at δ 11.74 and 8.98 ppm for (NH) proton (D2O exchangeable) and the aldimino proton
(CH=N) respectively, followed by the protons of pyrazolo[3,4-b]quinoxaline base moiety as
two doublets at δ 8.27 and 8.15 ppm (J7,8 = 7.65 Hz and J5,6 = 8.4 Hz) for H-5 and H-8, then
two triplets at δ 7.94 and 7.86 ppm (J = 7.65 Hz and J = 6.85 Hz) for H-6 and H-7, and the
protons of 1-phenyl group appeared as a doublet at δ 8.34 ppm (J = 7.65 Hz) for the two
protons in ortho-positions, a triplet at δ 7.60 ppm (J = 7.65 Hz) for the two protons in metaposition
and a triplet at δ 7.37 ppm (J = 8.45 Hz) for the proton in para-position. The proton
at position-4 in the furan ring appeared as a singlet at δ 6.89 ppm. The sugar region showed
the 1’-OH as a multiplet at δ 5.21-5.24 ppm and the other hydroxyl signals 2’-OH and 3’-OH
appeared as a broad singlet and doublet at δ 4.83 and 4.55 ppm (J3’,OH = 6.15 Hz),
respectively, and 4’-OH as a multiplet at δ 4.35-4.46 ppm. After deuteration protons of
hydroxyl groups disappeared and H-1’ was shown as a broad singlet at δ 4.83 ppm and H-2’,
H-3’ and the two geminal protons (H-4’a and H-4’b) appeared as a multiplet at δ 3.54-3.60
ppm. The methyl protons at position-2 in the furan ring appeared as a singlet at δ 2.57 ppm;
(Tables 2 and 3; Figures 3, 4, 5 and 6).