“…In particular, grayanoids with a wide spectrum of biological activities, such as sodium-channel-modulating2, analgesic3, sedative4, and insect antifeedant activities5, have been isolated from plants of the Rhododendron genus in recent years. Ten types of grayanane-related carbon skeletons have been reported, including grayanane (A- nor -B- homo ent -kaurane)6, 1,5-secograyanane7, 3,4-secograyanane8, 9,10-secograyanane9, 1,10:2,3-disecograyanane10, leucothane (A- homo -B- nor grayanane)11, kalmane (B- homo -C- nor grayanane)12, 1,5-seco kalmane13, micranthane (C- homo grayanane)14, and mollane (C- nor -D- homo grayanane)15. We previously reported mollolide A, a grayanoid with a new 1,10:2,3-disecograyanane skeleton10, and mollanol A, the first example with a C- nor -D- homo grayanane carbon skeleton15, from Rhododendron molle G. Don, a plant that is used in traditional Chinese medicine as an anodyne and anesthetic16.…”