Hydroxypyridonate and hydroxypyrimidinone chelating agents
申请人:Raymond N. Kenneth
公开号:US20050008570A1
公开(公告)日:2005-01-13
The present invention provides hydroxypyridinone and hydroxypyrimidone chelating agents. Also provides are Gd(III) complexes of these agents, which are useful as contrast enhancing agents for magnetic resonance imaging. The invention also provides methods of preparing the compounds of the invention, as well as methods of using the compounds in magnetic resonance imaging applications.
Hetero-Tripodal Hydroxypyridonate Gadolinium Complexes: Syntheses, Relaxometric Properties, Water Exchange Dynamics, and Human Serum Albumin Binding<sup>1</sup>
作者:Marlon K. Thompson、Dan M. J. Doble、Luke S. Tso、Serena Barra、Mauro Botta、Silvio Aime、Kenneth N. Raymond
DOI:10.1021/ic048607u
日期:2004.12.1
The synthesis and relaxometric properties of hetero-tripodal hydroxypyridonate-terephthalamide gadolinium (Gd3+) chelates with differing structural features for probing human serum albumin (HSA) interactions are reported. The Gd3+ complexes are divided into two series. The first series (3-5) features a benzyl derivative connected to the hydroxypyridonate (HOPO) moiety. The second series of complexes (6-10) has the common feature of a poly(ethylene glycol) (PEG) attached to the terephthalamide (TAM) moiety and is nonbenzylated. The water exchange of the complexes is in the fast exchange regime with rates (k(ex)) in the range 0.45-1.11 x 10(8) s(-1). The complexes have a moderate interaction with HSA with association constants (K-A's) in the range 0.7-8.6 x 10(3) M-1. Protein binding results in an enhancement in proton relaxivity from 7.7-10.4 mM(-1) s(-1) (r(1p)) to 15-29 mM(-1) s(-1) (r(1p)(b)). It is concluded that the interaction of the complexes with HSA (i) is enhanced by the presence of benzyl groups, (ii) is entropically driven, and (iii) results in a lower hydration number (q).