紫外線照射によるサイロキシンの光分解に関する研究

抄録

1. Ultraviolet irradiation of thyroxine, diiodotyrosine, and their analogous compounds was carried out to elcidate the process of photodegradation of thyroxine by ultraviolet ray. 2. For separation and detection of the degraded products, measurement of ultraviolet and infrared absorption spectra, and paper chromatography, thin-layer chromatography, and column chromatography were carried out. 3. Experimental results revealed that the irradiation of ultraviolet ray to thyroxine liberated iodine at first and then cleaved the ether bond in the molecule, and liberated α-phenyl ring from thyroxine. Triiodothyronine, diiodotyrosine, monoiodotyrosine, tyrosine, phenylalanine, serine, alanine, and glycine were detected as the photodegradation products. 4. Production of diiodotyrosine from ultraviolet ray irradiated thyroxine was confirmed by the measurement of infrared absorption spectrum. 5. The fact that thyronine or tyrosine which lacked iodine in the molecule was more resistant than iodoamino acids to ultraviolet ray irradiation suggested that instability of thyroxine and related compounds to ultraviolet ray was due to the liberation of iodine from these compounds.