describe an efficient and scalable synthesis of 4-carbomethoxy-6,6′-dimethyl-2,2′-bipyridine starting from easily available substituted 2-halopyridines and based on the application of modified Negishi cross-coupling conditions. This compound is a versatile starting material for the synthesis of 4-functionalized 2,2′-bipyridines bearing halide, alcohol, amine, and other functionalities, suitable for conjugation
In the design of dual-imaging probes, the first functionalized and neutral heterobimetallic Re(I)-Gd(III) complex, highly soluble in aqueous solutions, has been prepared. This system exhibits interesting photo-physical properties (lambda(em) = 578 nm, = phi = 1.4%) for optical imaging and substantial higher relaxivity (r(1) - = 6.6 mM(-1) s(-1) at 0.47 T and 37 degrees C) than the clinically used MRI contrast agents. Moreover, this system incorporates an aromatic ester functionality suitable for bioconjugation. (c) 2013 Elsevier Ltd. All rights reserved.
Development of a new radioligand for cholecystokinin receptor subtype 2 scintigraphy: From molecular modeling to in vivo evaluation
To improve the targeting to tumors expressing the cholecystokinin receptor subtype 2 (CCK2R) with limited kidney uptake, we synthesized a novel cholecystokinin C-terminal tetrapeptide (CCK4)-based derivative conjugated to an original bipyridine-chelator (BPCA), In-111-BPCA-(Ahx)(2)-CCK4. To our knowledge this is the first CCK4-based radioligand that presents a high affinity for the CCK2R, a high and specific tumor uptake, a low renal accumulation and a very good visualization of tumors in vivo compared with an internal control, (111)Indium-trans-cyclohexyldiethylenetriaminepenta-acetic acid-cholecystokinin octapeptide (In-111-CHX-A ''-DTPA-CCK8). These properties make In-111-BPCA-(Ahx)(2)-CCK4, a promising candidate for imaging and peptide receptor radionuclide therapy of CCK2R positive tumors. (C) 2010 Elsevier Ltd. All rights reserved.