128135-40-0Relevant academic research and scientific papers
Potent and fully noncompetitive peptidomimetic inhibitor of multidrug resistance P-glycoprotein
Arnaud, Ophélie,Koubeissi, Ali,Ettouati, Laurent,Terreux, Rapha?l,Alamé, Ghina,Grenot, Catherine,Dumontet, Charles,Di Pietro, Attilio,Paris, Jo?lle,Falson, Pierre
supporting information; experimental part, p. 6720 - 6729 (2010/11/16)
Nα-Boc-l-Asp(OBn)-l-Lys(Z)-OtBu (reversin 121, 1), an inhibitor of the P-gp ABC transporter, was used to conceive compounds inhibiting the drug efflux occurring through the Hoechst 33342 and daunorubicin transport sites of P-gp, respectively H and R sites. Replacement of the aspartyl residue by trans-4-hydroxy-l-proline (4(R)Hyp) gave compounds 11 and 15 characterized by half-maximal inhibitory concentrations (IC50) of 0.6 and 0.2 μM, which are 2-and 7-fold lower than that of the parent molecule. The difference in IC50 between 11 and 15 rests on the carbonyl group of the peptidyl bond, reduced in 15. Those compounds are rather specific of P-gp, having no or limited activity on MRP1 and BCRP. 15 displayed no marked cytotoxicity up to 10-fold its IC50. Importantly, 15 equally inhibited the Hoechst 33342 and daunorubicin effluxes through a typical noncompetitive inhibition mechanism, suggesting its binding to a site different from the H and R drug-transport sites.
Synthesis of acyclic and dehydroaspartic acid analogues of Ac-Asp-Glu-OH and their inhibition of rat brain N-acetylated α-linked acidic dipeptidase (NAALA dipeptidase)
Subasinghe,Schulte,Chan,Roon,Koerner,Johnson
, p. 2734 - 2744 (2007/10/02)
The following structural and conformationally constrained analogues of Ac-Asp-Glu-OH (1) were synthesized: Ac-Glu-Glu-OH (2), Ac-D-Asp-Glu-OH (3), Ac-Glu-Asp-OH (4), Ac-Asp-Asp-OH (5), Ac-Asp-3-aminohexanedioic acid (6), Ac-3-amino-3-(carboxymethyl)propanoyl-Glu-OH (7), N-succinyl-Glu-OH (8), N-maleyl-Glu-OH (9), N-fumaryl-Glu-OH (10), and Ac-Δ(z)Asp-Glu-OH (11). These analogues were evaluated for their ability to inhibit the hydrolysis of Ac-Asp-[3,4-3H]-Glu-OH by N-acetylated α-linked acidic dipeptidase (NAALA dipeptidase) in order to gain some insight into the structural requirements for the inhibition of this enzyme. Analogues 4-6 and 9 were very weak inhibitors of NAALA dipeptidase (K(i) > 40 μM), while 2, 3, and 7 with K(i) values ranging from 3.2-8.5 μM showed intermediate inhibitory activity. The most active inhibitors of NAALA dipeptidase were compounds 8, 10, and 11 with K(i) values of 0.9, 0.4, and 1.4 μM, respectively. These results suggest that the relative spacing between the side chain carboxyl and the α-carboxyl group of the C-terminal residue may be important for binding to the active site of the enzyme. They also indicate that the χ1 torsional angle for the aspartyl residue is in the vicinity of 0°.
