Esters derived from trans-4-methoxycinnamic acid are effective absorbers of UV radiation. The starting material was trans-4-methoxycinnamic acid and 3,5dimethoxybenzoic acid methyl ester in isolated avenanthramide alkaloids synthsis. trans-4-Methoxycinnamic acid was converted into its acid chloride (yield 98%) with thionyl chloride. Employed in organic synthesis of pharmaceutical intermediates, synthetic anti-adrenergic drugs esmolol, cosmetics ultraviolet absorption. Esters derived from trans-4-methoxycinnamic acid are effective absorbers of UV radiation. The starting material was trans-4-methoxycinnamic acid and 3,5dimethoxybenzoic acid methyl ester in isolated avenanthramide alkaloids synthsis. trans-4-Methoxycinnamic acid was converted into its acid chloride (yield 98%) with thionyl chloride. Employed in organic synthesis of pharmaceutical intermediates, synthetic anti-adrenergic drugs esmolol, cosmetics ultraviolet absorption.