Blood platelet aggregation inhibitor

Therapeutic Function Blood platelet aggregation inhibitor... 

The patent literature covers many pyridazine derivatives claimed as blood platelet aggregation inhibitors and antithrombotic agents. The interest has been focused mainly on 6-aryl-4,5-dihydro-3(2//)-pyridazinones. In these compounds the aryl substituent has been varied within a wide range. Thus, dihydro-pyridazinones bearing a substituted or heterocycle-fused phenyl group at C-6 (60, R R2,R3 = H, alkyl Ar = substituted Ph) [34, 110-112,205-233] as well as various heteroaryl substituted congeners (61, R1, R2, R3 = H, alkyl Ar = pyridyl, thienyl, pyrrolyl, pyrazolyl) [234-241] have been prepared in search of novel antithrombotics. 

Compounds 5 are used as neoplasm inhibitors (89EGP270711) and 14 as vasodilators, anticholesteremics, and blood platelet aggregation inhibitors [81JAP(K)81/127383]. Significant activity against histamine-induced bron-... 

CNS activity has been attributed to 3-alkyl-3,6-dihydro-2//-l,3,4-oxadiazin-2-ones <86EJM403>, and 5-aryl-3,6-dihydro-2//-l,3,4-oxadiazin-2-ones <93JAP(K)05 148250) are blood platelet aggregation inhibitors. 

Ozaki and co-workers prepared an extensive series of 5-aryl(heteroaryl)-4-oxazolecarboxylic acid methyl esters 368 (20 compounds) from acylation of methyl isocyanoacetate, followed by in situ cyclization (Scheme 1.100). These compounds were elaborated further and evaluated as blood platelet aggregation inhibitors. 

C10H12CIN5O4 301.689 Nucleoside antibiotic. Isol. from Strepto-myces rishiriensis. Blood platelet aggregation inhibitor. Weakly active against gram-positive and -negative bacteria. Nucleoside transporter substrate. Cryst. + V2 H2O. Sol. H2O fairly sol. MeOH poorly sol. Me2CO, hexane. 

CioHisClNfiOfiS 380.768 From Streptomyces rishiriensis. Blood platelet aggregation inhibitor. Active against gram-positive and -negative bacteria. Herbicide. Needles. 

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