Autor:	Johann G. Leonhartsberger, Heinz Falk
Rok vydání:	2002
Předmět:	chemistry.chemical_compound Deprotonation Chemistry Computational chemistry Proton NMR Protonation General Chemistry Electrospray ms Photochemistry Hypericin
Zdroj:	Monatshefte fuer Chemie/Chemical Monthly. 133:167-172
ISSN:	0026-9247
DOI:	10.1007/s706-002-8246-x
Popis:	The protonation and deprotonation behaviour and the assignment of pK a values of hypericin are reviewed and discussed. Three experiments (electrospray MS, 1H NMR, acid–base indicator equilibria) provided additional evidences for the assignment of pK a values of −5 and −6 to mono- and diprotonation at the carbonyl groups of hypericin, of pK a = 2 to monodeprotonation at the bay-region, and of pK a = 11 to dideprotonation at the bay- and peri-regions.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::fbab2bfc8d89ca9ecb46199b89814048 https://doi.org/10.1007/s706-002-8246-x Zobrazit plný text záznamu Full text from SpringerLink