Sulfone
II
was synthesized via oxidation of ethyl 2-[5-bromo-2,4-dihydro-3-oxo-2-(thietanyl-3)-1,2,4-triazolyl- 4]acetate (
I
) by H
2
O
2
. Hydrolysis of esters
I
and
II
synthesized 2-[5-bromo-2,4-dihydro- 3-oxo-2-(thietanyl-3)-1,2,4-triazolyl-4]- and 2-[5-bromo-2,4-dihydro-3-oxo-2-(1,1-dioxothietanyl-3)-1,2,4- triazolyl-4]acetic acids
III
and
IV
, respectively.Water-soluble salts
V
and
VI
were prepared by reacting acids
III
and
IV
with alkali-metal hydroxides and amines. The structures of the synthesized compounds were confirmed IR and NMR spectroscopic data. The antiplatelet and anticoagulant activity of the synthesized compounds was studied
in vitro
based on predictions of the PASS computer program. Compounds
III
and
VIb
, which showed the absence of predicted toxic risks and were superior to the reference drug in the collagen-induced aggregation test, had the most pronounced antiplatelet activity (comparable to that of acetylsalicylic acid) in the ADP-induced aggregation test. The anticoagulant activity of the compounds was significantly inferior to that of heparin sodium. All synthesized compounds satisfied Lipinski’s rule-of-5.