Phosphorylation of 6-chloropurine riboside with phosphorus oxychloride and phosphorus trichloride gave a mixture of the two isomers, 6-chloropurine-riboside 2’,5‘-bisphosphate and 6-chloropurine-riboside 3‘,5‘-bisphosphate. Reaction with Iy6-diaminohexane followed by resolution of the isomeric mixture on a Dowex 1-X2 column yielded N6-(6-aminohexyl)-adenosine 2’,5’-bisphosphate and N6-(6-aminohexyl)-adenosine 3’,5‘-bisphosphate.The inhibition of several NADP+-dependent and NAD+-dependent dehydrogenases by N6-(6-aminohexyl)-adenosine 2’,5‘-bisphosphate, N6-(6-aminohexyl)-adenosine 3’,5’-bisphosphate and N6-(6-aminohexyl)-adenosine 5’-monophosphate was examined.These three AMP-analogues were attached to Sepharose 4B by the cyanogen bromide method and the binding of several NAD(P)+-dependent enzymes were investigated. NADP+-dependent enzymes were bound to Sepharose substituted with N6-(6-aminohexyl)-adenosine 2’,5‘-bisphosphate, whereas NAD+-dependent enzymes were not bound under the same conditions. Conversely, when N6-(6-aminohexy1)-adenosine 5‘-monophosphate was used as the immobilised ligand only the NAD+- dependent enzymes were bound, as well as glucose-6-phosphate dehydrogenase showing weak affinity. These observations strongly suggest that these two immobilised analogues represent true biospecific and group-specific adsorbents. The enzymes were eluted with their complementary nucleotides, NAD(H) and NADP(H). These techniques were utilised to purify several NADPf-dependent enzymes from a crude Candida utilis extract by chromatography on the new biospecific adsorbent.