Effects of various 2-amino-6-alkyldithiopurines on brain specific [3H]diazepam binding

Various derivatives of 2-amino-6- methylthiopurine with substituents at the 6-position of purine were tested for their abilities to displace [3H]diazepam binding to rat brain membranes. The potency was dependent on the carbon chain-length in the 6-position of purine. Among the derivatives tested, 2-amino-6-n- pentyldithiopurine had the highest potency, with a Ki value of 0.92 microM.