The Preparation of Thyroxine Analogs

Abstract

Variation of the side chain in tryptophan as exemplified by indoleacrylic acid produces a compound which interferes with the growth-stimulating action of tryptophan (1). In order to determine whether such a variation in structure among amino acids is general in producing antagonistic effects, ^-substituted acrylic acids which have the same diphenyl ether nucleus as thyroxine have been synthesized for testing as possible antithyroid agents.3,5-Diiodo-4-(4'-methoxyphenoxy)cinnamic acid (II, X = I) and 3,5-dibromo-4-(4'-methoxyphenoxy)cinnamic acid (II, X = Br) were prepared by condensing 3,5-diiodo-4-(4'-methoxyphenoxy)benzaldehyde (I, X = I) and 3,5-dibromo-4-(4'-methoxyphenoxy)benzaldehyde (I, X = Br) (2) with malonic acid in the presence of pyridine and piperidine. SUMMARY 1. 3,5-Diiodo-4-[4'-hydroxy-3',5'-diiodophenoxy]cinnamic acid and related compounds have been prepared for testing as possible antithyroid agents.2. Ultraviolet absorption data and polarographic data are presented as proof for the unsaturation in this compound.

Structure and electronic absorption spectra of nematogenic alkoxycinnamic acids – a comparative study based on semiempirical and DFT methods

“…The experimental studies show that cinnamic acid exhibits two strong absorptions at 220 nm and 267 nm (λ max ) [30]. The present calculations have been carried out on cinnamic acid derivatives (nOCAC, n=2, 4, 6, 8) to study their ultraviolet stability in the light of the shift of absorption wavelength with respect to the different substitution of various alkoxy groups.…”