6
VELUGULA ET AL.
N-carbamoyl Oxcarbazepine as a pale yellow solid (1 g).
1H NMR (500 MHz, DMSO-d6): 3.80 (d, 1H), 4.45 (d, 1H),
7.15 (brs, 1H), 7. 48 (brs, 1H), 7.33–7.67 (m, 7H), 7.94 (d,
1H), 8.27 (brs, 1H); 13C NMR (75 MHz, D.M.S.O) 38.65–
40.32, 48.30, 103.82, 126.96, 127.57, 128.14, 129.72,
130.00, 130.55, 132.74, 133.46, 134.08, 134.93, 140.42,
142.61, 152.56, 153.77, 192.12;IR (KBr): 3488, 3227, 2924,
1959, 852 cmÀ1; HRMS (ESI-QTOF) for C16H13N3O3 [M
+ H]+: m/z calcd: 296.1034; found:296.1038.
D.M.S.O) 38.66–40.23, 126.87, 127.01, 127.46, 128.76.
129.56, 129.73, 134.03, 141.27, 156.07, 192.38; IR(KBr)
3645, 3626, 2924, 1131, 1036, 1021, 882, 668 cmÀ1; HRMS
(ESI-QTOF) for C30H22N4O3 [M + H]+: m/z calcd:
487.1769; found: 487.1767.
ACKNOWLEDGMENTS
Our heartfelt gratitude to Dr. Syam Kumar U. K for his
constant support and guidance for this work. The authors
are grateful to the management of Aurobindo Pharma
Ltd., for supporting this work. co-operation from col-
leagues of Chemical Research Department and Analytical
Research department is highly appreciated.
4.3 | Synthesis of N-formyl
Oxcarbazepine (4)
Formic acid (24 g, 0.048 mol) was added drop wise to acetic
anhydride (44 g, 0.43 mol) at 25 ꢀC for 20 min. This reac-
tion mass was heated to 45–50ꢀC and stirred for 1 h. The
reaction mass was cooled to 25ꢀC, Oxcarbazepine (12 g)
was added and the reaction mass was heated to 55–60ꢀC
and stirred for 1 h. After completion of the reaction (moni-
tored by TLC), the reaction mass was cooled and quenched
with DM water. The precipitated product was extracted
with ethyl acetate (3 Â 300 ml). The combined organic
extract was washed with DM water, dried over sodium sul-
phate and concentrated to obtain a residue. This residue
was purified by column chromatography (100–200 mesh
size silica) using a mixture of 40% ethylacetate and hexane
as mobile phase to afford N-formyl Oxcarbazepine (3.5 gm)
DATA AVAILABILITY STATEMENT
Full Experimental details, 1H NMR spectra, 13C NMR
spectra, FTIR and HRMS data can be obtained via the
“Supplementary Content” section of the article's
web page.
ORCID
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1
as a colorless solid. H NMR (500 MHz, CDCl3): 3.89 (d,
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