الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present work includes the synthesis of some different
compounds derived from pyrrole. Thus on reaction of acetyl pyrrole
with CS2 it furnished the oxoketene gem-dithiol (2).Reaction of (2) with salicyaldehyde in acetonitrile as a solvent
and marble as a catalyst and gives 2-mercapto-3-(1-methyl-1Hpyrrole-
2-carbonyl)chromen-4-one (4) while on reaction the (2) with
cinnamaldehyde and ethylcyanoacetate in tetrahydrofuran and drops
of glacial acetic acid it furnishes 2-Mercapto-3-(1-methyl-1Hpyrrole-
2-carbonyl)-4-oxo-6-phenyl cyclohexa- methyl-1H-pyrrol-1-2yl)-2-oxoethylidene]-3a,7a-dihy-drobenzo[1,3]
dithiol-4,7-dione (6); 2-[2-(1-methyl-1H-pyrrol-1-2yl)-2-oxoethylidene]-
3a,9a-dihydronaphtho[2,3-d][1,3]dithiol-4,9-dione (7); 2-(2,4-dithiabicyclo[
3.2.1]octa-6-en-3-ylidene)-1-(1-methyl-1H-pyrrol-2yl)
ethanone (8) and 2-[2-(1-m-ethyl-1-H-pyrrol-2-yl)-2-oxo-ethylidene]
dihydro[1,3]dithiolo[4,5-c]furan-4,6-dione (9) respectively.2,5- Treatment of (2) with malononitrile in THF/AcOH it gives
thiopyrane derivative (10) while on reaction of dithiol (2) with
thiosemicarbazide in refluxing ethanol, 3-mercapto-3-thiosemicarbazide-
1-(2-pyrr-olyl)-2-propenone (11) was obtained. Reaction of
dithiol (2) with indole in methylene chloride in the presence of monochloroacetic
acid it gave 3-(1H-indol-3-yl)-3-mercapto-1-(1-methyl-
1H-pyrrol-2-yl)propenone (12). Formylation of 1,2-dithione-3-thione (3) in the presence of DMF/
POCl3 it gives 5-(1-methyl-1H-pyrrol-2-yl)-3-thioxo-3H-[1,2]dithiol-
4-carbaldehyde (17). When 1,2-dithione-3-thione (3) was heated
under reflux with p-benzoquinone or 2,3-dichloro-1,4-naphthoquinone
it gives 2-[2-(1-methyl-1H-pyrrol-2-yl)-2thioxoethylidene]-3a,7adihydrobenzo[
1,3]dithiol-4,7-dione (18) and 3a,3a-dichloro-2-[2-(1-
methyl-1H-pyrrol-2-yl)-2-thioxoethylidene]-3a,9a-dihydronaphtho[2,
3-d][1,3]dithiol-4,9-dione (19) respectively.dienecarbonitrileReaction of (3) with salicyaldehyde in acetonitrile in the presence
of marble it gives mercapto-3-(1-methyl-1H-pyrrole-2-carbothioyl)
chromen-4-one (20). Treatment of (3) with cinnamaldehyde and ethyl
acetoacetate in THF/AcOH it gives 1-[3-mercapto-4-(1-methyl-1Hpyrrole-
2-carbothioyl)-biphenyl-2-yl]ethanone (21).α-Oxo ketene dithioacetals, which bear a carbonyl group at the α-C atom, are
versatile intermediates in organic synthesis. α-Oxo ketene dithioacetals reacts as 1,3-
electrophilic three-carbon synthones. Oxoketene dithioacetals behaves on the bases
that, the α-carbon of ketene dithioacetals is reactive towards electrophiles and this
electrophilic susceptibility makes the functionalization of ketene dithioacetals a
convenient tool for the construction of diverse ketene dithioacetal scaffolds and other
useful building blocks. These arylketones are well known for their use as a building
block for the synthesis of various pharmaceuticals.(1-8) These are α,β-unsaturated
carbonyl compounds with two electron-donating alkylsulafanyl groups on one end
and an electron-withdrawing aroyl group at the other end of the double bond, i.e., they
are ”push-pull” alkenes.