ABSTRACT
<p><b>AIM</b>To study the synthesis of 5-(3'-indolyl)-oxazoles and their antioxidative activity.</p><p><b>METHODS</b>The amides were prepared from tryptophan and different acid derivatives by the catalytic dehydration of dicyclohexyl carbodiimide (DCC). The characteristic heterocyclic ring system of 5-(3'-indolyl)-oxazoles was constructed by oxidative cyclization of amide, using dicholorodicyanoquinone (DDQ). Their antioxidative activity in vitro was tested using DPPH system.</p><p><b>RESULTS</b>Eleven 2-substituted phenyl-5-(3'-indolyl)-oxazoles were prepared, the compounds 21 and 22 have shown antioxidative activity 3-4 times stronger than that of Vit E, and the compound 29 showed antioxidative activity almost as same as Vit E.</p><p><b>CONCLUSION</b>Three 5-(3'-indoyl)-oxazole compounds synthesized showed potent antioxidative effect and they would be a good antioxidants.</p>
Subject(s)
Antioxidants , Chemistry , Indoles , Chemistry , Molecular Structure , Oxazoles , ChemistryABSTRACT
<p><b>AIM</b>To isolate and purify gonyautoxins from Alexandrium mimutum Halim Amtk2 strain.</p><p><b>METHODS</b>The ethanol extracts of culture Alexandriun minutum Halim Amtk2 were isolated by means of gel filtration chromatography, the toxin fraction obtained was then purified by ion exchange chromatography.</p><p><b>RESULTS</b>From 100 liter of cultivation liquid of Alexandrium mimutum Halim Amtk2 (6.74 +/- 0.31) x 10(9) cells were obtained. The ethanol extracts of Alexandriun minutum Halim purified by gel filtration chromatography obtained gonyautoxins mixture 29.59 mg. 4.06 mg of the mixture was further purified by two steps of ion exchange chromatography, and obtained pure GTX-4 (0.40 +/- 0.002) mg, GTX-1 (5.95 +/- 0.03) x 10(-2) mg, GTX-3 (6.92 +/- 0.05) x 10(-4) mg and GTX-2 (0.11 +/- 0.005) mg.</p><p><b>CONCLUSION</b>Pure gonyautoxins can be obtained by means of gel filtration chromatography and ion exchange chromatography from ethanol extracts of cultured Alexandriun minutum Halim Amtk2 strain.</p>