''Abbreviated'' NAD(+) analogues containing a phosphonate function

''Abbreviated'' NAD(+) analogues with anionic phosphonate function as a part of the link between the adenine and nicotinamide moieties, 9-(2-phosphonomethoxyethyl)adenine 2-(3-carbamoylpyridinium)ethyl ester (1a), (R)- and (S)-9-(2-phosphonomethoxypropyl)adenine 2-(3-carbamoylpyridinium)ethyl ester (1b and 1c), (RS)-9-(3-hydroxy-2-phosphonomethoxypropyl)adenine 2-(3-carbamoylpyridinium)ethyl ester (1d), and (S)- and (R)-1-[3-(adenin-9-yl)-2-phosphonatomethoxypropyl]-3-carbamoylpyridinium (2a and 2b), were prepared by multistep syntheses using the Zincke reaction in the last step.