EXPERIMENTAL
The IR spectra of the synthesized compounds were recorded on an IKS 29 instrument (in nujol). The
1H NMR spectra were recorded on a Bruker WP-100SY (100 MHz) instrument [for compounds 6i,8c,10a,b on a
Bruker WM-250 (250.13 MHz)] in DMSO-d6, internal standard was Me4Si. The course of reactions was
monitored by TLC (Silufol UV 254, acetone–heptane 3 : 5, visualization by iodine vapor).
5-Acetyl-3-cyano-6-methylpyridine-2(1H)-thione (4). A mixture of ethoxymethyleneacetylacetone 1
(15 g, 96 mmol), cyanoacetamide 2 (9.6 g, 96 mmol), and N-methylmorpholine (10.8 ml, 96 mmol) in abs.
ethanol was stirred for 2 h at 25°C. The precipitate formed was filtered off, washed with abs. ethanol, and with
hexane. Compound 4 was obtained, identical with that described previously in [7].
5-Acetyl-3-cyano-6-methyl-2-(R-methylthio)pyridines 6a-m. Thione 4 (1 g, 5.2 mmol) was dissolved
in DMF (8 ml) and 10% KOH solution (2.9 ml, 5.2 mmol) was added with stirring. The appropriate halogen
derivative 5a-m (5.2 mmol) was introduced into the reaction mixture after 5 min, the mixture was filtered
through a folded filter, and stirred for 4 h. The precipitate was filtered off, and washed with ethanol.
Compounds 6a-m were obtained (Table 1).
5-Acetyl-3-amino-6-methyl-2-(R-carbonyl)thieno[2,3-b]pyridines (8a-c). Thione 4 (1 g, 5.2 mmol)
was dissolved in DMF (8 ml) and 10% KOH solution (2.9 ml, 5.2 mmol) was added with stirring. After 5 min
the appropriate chloride 7a-c (5.2 mmol) was introduced into the reaction mixture, and stirring continued for
0.5 h, then 10% KOH solution (2.9 ml) was again added to the reaction mixture. The solution was stirred for
4 h. The precipitate was filtered off, and washed with ethanol. Compounds 8a-c were obtained (Table 1).
Di(5-acetyl-3-cyano-6-methyl-2-pyridinylthio)alkanes (10a,b). Thione 4 (1 g, 5.2 mmol) was
dissolved in DMF (8 ml) and 10% KOH solution (2.9 ml, 5.2 mmol) was added with stirring. After 5 min the
appropriate dibromoalkane 9a,b (2.6 mmol) was added to the reaction mixture, the mixture was filtered through
a folded filter, and stirred for 4 h. The precipitate was separated, and washed with ethanol. Compounds 10a,b
were obtained (Table 1).
5-Bromoacetyl-3-cyano-6-methyl-2-methylthiopyridine (11). The 2-methylthiopyridine 6a (1 g,
4.8 mmol) was dissolved in glacial acetic acid (8 ml) and bromine (0.25 ml, 4.8 mmol) was introduced to the
solution dropwise with stirring in the light. The reaction mixture was stirred until decolorized, then cooled with
ice. The resulting precipitate was filtered off, and washed with ethanol. Compound 11 was obtained (Table 1).
5-Anilinoacetyl-3-cyano-6-methyl-2-methylthiopyridine (12). The bromoacetylpyridine 11 (1 g,
3.9 mmol) was dissolved in ethanol (5 ml) and aniline (0.44 ml, 4.8 mmol) was added with stirring. The reaction
mixture was stirred for 2 h. The resulting solid was filtered off, and washed with ethanol. Pyridine 12 was
obtained (Table 1).
3-Cyano-5-(2-cyanomethyl-4-thiazolyl)-6-methyl-2-methylthiopyridine (13).
A
mixture of
bromoacetyl-pyridine 11 (1 g, 3.9 mmol) and cyanothioacetamide 2 (0.48 g, 4.8 mmol) in DMF (8 ml) was
stirred for 2 h. The precipitate formed was filtered off, and washed with ethanol. Compound 13 was obtained
(Table 1).
3-Cyano-2-(3-cyano-6-methyl-2-methylthio-5-pyridylcarbonylmethylthio)-5-ethoxycarbonyl-6-
hydroxypyridine (15). A mixture of thiolate 14 (1 g, 3 mmol) and bromide 11 (0.88 g, 3 mmol) in ethanol
(10 ml) was brought to boiling and filtered through a folded filter. The solid which precipitated on cooling the
filtrate was separated, and washed with ethanol. Pyridine 15 was obtained (Table 1).
3-Amino-2-(3-cyano-6-methyl-2-methylthio-5-pyridylcarbonyl)-5-ethoxycarbonyl-6-hydroxythieno-
[2,3-b]pyridine (16). Compound 15 (1 g, 2.3 mmol) was dissolved in DMF (8 ml) and 10% KOH solution
(1.3 ml, 2.3 mmol) was added with stirring. The reaction mixture was stirred for a further 2 h. The precipitate
was filtered off, and washed with ethanol. Compound 16 was obtained (Table 1).
The work was carried out with the financial support of the Russian Fund for Fundamental Investigations
(project No. 99-03-32965)
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