Promotion of cyclization of linear pentapeptides and heptapeptide by different univalent metal ions
Yun-hua Ye1, Mian Liu, Yan-chun Tang
1Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education, Department of Chemistry, Peking University, Beijing 100871, China. yhye@pku.edu.cn
Chemical Communications (Cambridge, England)
|July 18, 2002
Abstract:
Univalent metal ions such as Na+, K+ and Cs+ can enhance not only the cyclization yields of some linear pentapeptides and heptapeptide but also their cyclization rates while some bivalent and trivalent metal ions such as Mg2+, Ca2+, Zn2+, Fe2+, Ni2+ and Cr3+ elevate neither the cyclization yields nor the cyclization rates and some of them prevent the cyclization.
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