NOVELTY - Preparation of 2-(((1R)-1-(7-methyl-2-(morpholin-4-yl)-4-oxo-4H-pyrido(1,2-a)pyrimidin-9-yl)ethyl)amino)benzoic acid (I) involves performing amination reaction of 9-acetyl-7-methyl-2-(morpholin-4-yl)-4H-pyrido(1,2-a)pyrimidin-4-one with R-t-butyl-sulfonamide, performing reduction reaction, obtaining 9-(1R-aminoethyl)-7-methyl-2-(morpholin-4-yl)-4H-pyrido(1,2-a)pyrimidin-4-one, performing condensation reaction with ester group-containing compound (IX) in presence of catalyst, cocatalyst and alkali accelerator, obtaining morpholine derivative (X) and performing hydrolysis process.    USE - Preparation of 2-(((1R)-1-(7-methyl-2-(morpholin-4-yl)-4-oxo-4H-pyrido(1,2-a)pyrimidin-9-yl)ethyl)amino)benzoic acid used as antiplatelet medicine.    ADVANTAGE - The method provides 2-(((1R)-1-(7-methyl-2-(morpholin-4-yl)-4-oxo-4H-pyrido(1,2-a)pyrimidin-9-yl)ethyl)amino)benzoic acid by simple, economical and environmentally-friendly process.    DETAILED DESCRIPTION - Preparation of 2-(((1R)-1-(7-methyl-2-(morpholin-4-yl)-4-oxo-4H-pyrido(1,2-a)pyrimidin-9-yl)ethyl)amino)benzoic acid of formula (I) involves carrying out ethyl or isopropyl nucleophilic substitution reaction of propionaldehyde in presence of sodium methylate, sodium hydride or lithium diisopropylamide and methyl formate, performing cyclization reaction with acetoacetamide, obtaining 3-acetyl-5-methyl-2-pyridone, performing chlorination reaction of 3-acetyl-5-methyl-2-pyridone in presence of chlorinating agent, obtaining 2-chloro-3-acetyl-5-methyl-pyridine, performing amino group-substitution reaction of 2-chloro-3-acetyl-5-methyl-pyridine with zinc bis(trimethylsilyl)amide in presence of tris(dibenzylideneacetone)dipalladium or formamide and copper sulfate, obtaining 2-amino-3-acetyl-5-methylpyridine, performing cyclization reaction of 2-amino-3-acetyl-5-methylpyridine with 4,4'-(1,3-dioxo-1,3-propanediyl)bis-morpholine in presence of p-toluenesulfonic acid, obtaining 9-acetyl-7-methyl-2-(morpholin-4-yl)-4H-pyrido(1,2-a)pyrimidin-4-one, performing amination reaction of obtained compound with R-t-butyl-sulfonamide in presence of titanium tetraethoxide, performing reduction reaction, obtaining 9-(1R-aminoethyl)-7-methyl-2-(morpholin-4-yl)-4H-pyrido(1,2-a)pyrimidin-4-one, performing condensation reaction with ester group-containing compound of formula (IX) in presence of catalyst, cocatalyst and alkali accelerator, obtaining morpholine derivative of formula (X) and performing hydrolysis process.    X=F, Cl, Br or I;and    R=H or methyl, ethyl, n-propyl, isopropyl, allyl, n-butyl or tert-butyl.