Crystal structure of koraiol — A sesquiterpene alcohol with a new type of carbon skeleton from the oleoresin ofPinus koraiensis

An x-ray structural investigation has been made of a new sesquiterpene alcohol — koraiol — in the form of its complex with pyridine (2:1). The cyclobutane rings are nonplanar and the foldings of rings A and B amount to 17 and 31°, respectively. The seven-membered ring has the chair form.