Covering: 1978–2000. Previous review: R. J. Ferrier, Adv. Carbohydr. Chem. Biochem., 1978, 35, 31–80.

The science of cannabis and cannabinoids encompasses a wide variety of scientific disciplines and can appear daunting to newcomers to the field. The encroachment of folklore and ‘cannabis culture’ into scientific discussions can cloud the situation further. This Primer Review is designed to give a succinct overview of the chemistry of cannabis and cannabinoids. It is hoped that it will provide a useful resource for chemistry undergraduates, postgraduates and their instructors, and experienced chemists who require a comprehensive and up to date summary of the field. The Review begins with a brief overview of the history and botany of cannabis, then goes on to detail important aspects of the chemistry of phytocannabinoids, endocannabinoids and synthetic cannabinomimetics. Other natural constituents of the cannabis plant are then described including terpenes and terpenoids, polyphenolics, alkaloids, waxes and triglycerides, and important toxic contaminants. A discussion of key aspects of the pharmacology associated with cannabinoids and the endocannabinoid system then follows, with a focus on the cannabinoid receptors, CB1 and CB2. The medicinal chemistry of cannabis and cannabinoids is covered, highlighting the range of diseases targeted with cannabis and phytocannabinoids, as well as key aspects of phytocannabinoid metabolism, distribution, and delivery. The modulation of endocannabinoid levels through the inhibition of key endocannabinoid-degrading enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) is then discussed. The Review concludes with an assessment of the much touted ‘entourage effect’. References to primary literature and more specialised reviews are provided throughout.