143564-91-4Relevant academic research and scientific papers
Total synthesis of thiangazole
Akaji, Kenichi,Kiso, Yoshiaki
, p. 10685 - 10694 (2007/10/03)
A method for total synthesis of thiangazole (1), a tris-thiazoline- oxazole metabolite, is described. The key intermediate 9, a linear tetrapeptide amide composed of three S-benzyl-2-methylcysteine residues and a O-benzyl-threonine amide, was synthesized in 4 steps using 2-chloro-1,3- dimethyl-imidazolidium hexafluorophosphate(CIP)mediated activation. The successive thiazoline/oxazole rings were constructed by TiCl4mediated cycledehydration followed by acid-catalyzed Robinson-Gabriel reaction without difficulty.
Convergent synthesis of (-)-mirabazole B using a chloroimidazolidium coupling reagent, CIP
Kuriyama, Naohiro,Akaji, Kenichi,Kiso, Yoshiaki
, p. 8323 - 8334 (2007/10/03)
(-)-Mirabazole B (1), an alkaloid consisting of four successive thiazoline/thiazole rings, has been synthesized in a convergent route. The key intermediate, a linear tripeptide amide 13 composing of three S-benzyl-2-methylcysteine residues, was prepared u
Convergent synthesis of (-)-mirabazole C using a chloroimidazolidium coupling reagent, CIP
Akaji, Kenichi,Kuriyama, Naohiro,Kiso, Yoshiaki
, p. 3350 - 3357 (2007/10/03)
Convergent synthesis of (-)-mirabazole C (1), a tetra thiazoline/thiazole alkaloid isolated from blue-green alga, has been described. The successive thiazoline rings of (-)-mirabazole C were formed by a single-step cyclization mediated by TiCl4 treatment of tripeptide amide 4. Convergent synthesis of the key intermediate 33 derived from three 2-methylcysteine residues was first achieved using a newly developed coupling reagent, 2-chloro-1,3-dimethylimidazolidium hexafluorophosphate (CIP). The effectiveness of CIP for the coupling of α,α-dialkyl amino acids and the reaction pathway of the activation were clarified by the syntheses of model peptides containing an α,α-dimethylamino acid. A practical method of asymmetric synthesis of 2-methylcysteine by alkylation of 2,4-cis-oxazolidinone 23 has also been described.
