Spectroscopy and reactivity of zinc 20‐oxaporphyrin‐IX dimethyl ester

M. A. Hempenius*, J. H. Koek, J. Lugtenburg, R. Fokkens

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

11 Citations (Scopus)


A facile method of preparing zinc 20‐oxaprotoporphyrin‐IX dimethyl ester (1) from biliverdin‐IXα dimethyl ester has been found. According to NMR spectroscopy, the oxa substituent has a pronounced influence on the properties of the macrocyclic ring system. The 1H NMR spectrum reveals an aromatic structure and 13CNMR shows that in 1 a positive charge is delocalized, in agreement with the presence of one positive charge, and further that C‐1 and C‐19 have acquired the highest positive charge. This is corroborated by the reaction with nucleophiles, especially thiolates, leading to isolated adducts which could be well characterized. The adducts are the result of nucleophilic attack on the positions 1 and 19 exclusively, which agrees well with the charge on these positions in 1. The adducts show interesting spectroscopic properties. The study of oxaporphyrins and their nucleophilic adducts may contribute to a fuller understanding of the formation and properties of bile pigments.

Original languageEnglish
Pages (from-to)105-112
Number of pages8
JournalRecueil des Travaux Chimiques des Pays‐Bas
Issue number4
Publication statusPublished - 1987
Externally publishedYes


Dive into the research topics of 'Spectroscopy and reactivity of zinc 20‐oxaporphyrin‐IX dimethyl ester'. Together they form a unique fingerprint.

Cite this