FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to method of synthesis of aryloxyacetic acid of the general formula (I) 
where X means -C(Et)=C(Et)-; -CH(Et)- -CH(Et)- . Method involves condensation of phenol of the general formula (II) 
with haloidacetic acid ester in the presence of alkaline agent in medium of organic solvent or their mixture followed by acidification of reaction mixture and extraction of reaction products with 3-20% alkali aqueous solution, keeping obtained alkaline extract at 20-100 C for 8-12 h, neutralization to pH 6-8, separation of precipitated parent phenol, acidification to pH 1 and isolation of end product with yield 39-41%. Reaction is carried for a single stage. Product is used for preparing protein conjugates in development of immunohistochemical methods of hormones assay and it shows antioxidant and anti-inflammatory properties also. EFFECT: improved and simplified method, decreased reaction time.
