KM-233 is a drug which is an analogue of Δ8-tetrahydrocannabinol (THC), the less active but more stable isomer of the active component of Cannabis. km-233 differs from Δ8-THC by the pentylside chain being replaced by a 1,1-dimethylbenzyl group. It has high binding affinity in vitro for both the CB1 and CB2 receptors, with a CB2 affinity of 0.91nM and 13x selectivity over the CB1 receptor. In animal studies it has been found to be effective for the treatment of glioma, a form of brain tumor. A large number of related analogues are known where the 1,1-dimethylbenzyl group is substituted or replaced by other groups, with a fairly well established structure-activity relationship.
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