Russian Journal of General Chemistry, Vol. 75, No. 12, 2005, pp. 1962 1964. Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 12, 2005,
pp. 2052 2054.
Original Russian Text Copyright
2005 by Kadirova, Nuralieva, Alieva, Talipov, Tilyakov, Parpiev.
Synthesis and Crystal Structure
of 2-Aminoacetyl-1,3,4-thiadiazole
Sh. A. Kadirova*, G. A. Nuralieva*, M. A. Alieva*,
S. A. Talipov**, Z. G. Tilyakov**, and N. A. Parpiev*
* Ulugbek National University of Uzbekistan, Tashkent, Uzbekistan
** Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of Uzbekistan, Tashkent, Uzbekistan
Received November 19, 2004
Abstract 2-Aminoacetyl-1,3,4-thiadiazole was synthesized, and its structure was studied. In crystal, the
thiadiazole molecules form hydrogen-bonded endless one-dimensional chains related by the glide reflection
plane.
Proceeding with our research into 1,3,4-thiadiazole
derivatives [1 3] we synthesized 2-aminoacetyl-1,3,4-
thiadiazole that belongs to compounds known to ex-
hibit a broad-range biological and pharmacological
activity [4]. A series of 1,3,4-thiadiazole derivatives
was synthesized and studied mostly by means of H
and IR spectroscopy [5].
The X-ray analysis showed that single crystals of
compound II belong to the orthorhombic syngony.
Figure 1 presents the molecular structure of II, and
the table lists the interatomic distances and bond
angles. Compound II (Fig. 1), like previously studied
2-amino-5-phenyl- and 2-amino-5-(m-nitrophenyl)-
1,3,4-thiadiazoles [1, 2], have the N1, N2, and S1 lone
electron pairs conjugated with the double bonds of the
thiadiazole ring, as evidenced by the N1 C1, N2 C2,
and N1 N2 bond lengths of 1.283(5), 1.302(4), and
1.387(4) , respectively. The endocyclic N C bond
lengths are intermediate between the standard single
and double bond lengths. The imino N3 C2 and
1
Here we present the results of single-crystal X-ray
analysis of 2-aminoacetyl-1,3,4-thiadiazole (II) pre-
pared by the reaction of 2-amino-1,3,4-thiazole (I)
with acetic anhydride. The synthesis of acetyl deri-
vative II was performed by the procedure in [6] by
heating compound I in acetic anhydride. Therewith,
the yield of the final product was 76%.
N3 C3 [1.372(4) and 1.362(4)
] and C3=O1
[1.218(4) ] bond lengths are normal values. In whole
the molecule is planar, which is evidenced by the fact
that the molecule in crystal is in a special position,
viz. in the glide reflection plane.
N
N
+ Ac2O
H C
C NH2
S
I
In the crystal structure of thiadiazole II, as noted
above, the molecules are in special positions, i.e. glide
reflection planes perpendicular to the y axis. The
N
N
H C
C NHAc
AcOH
S
II
N2
The IR spectrum of compound II contains charac-
N1
teristic absorption bands at 1543 [ (C=N)] and
1439 cm
N3
C2
[
as(C=N)] and =N-N=, N=C sN, C=O, and
1
C4
C S absorption bands at 1040, 1564, 1684, and
1
634 cm , respectively [7].
C3
1
The H NMR spectrum of compound II shows
C1
downfield multiplet signals centered at 9.08 ppm,
that were assigned to the thiadiazole ring proton.
Methyl protons give a broadened singlet at
2.14 ppm and the imino group, a singlet at
12.4 ppm.
O1
S1
Fig. 1. Molecular structure of compound II and atom
numbering scheme.
1070-3632/05/7512-1962 2005 Pleiades Publishing, Inc.