New grayanol diterpenoid and new phenolic glucoside from the flowers of Pieris formosa

A new grayanol diterpenoid, grayanotoxin XXII (1), and a new phenolic glucoside, benzyl 2-hydroxy-4-O-[β-xylopyranosyl(1″ → 6′)-β-glucopyranosyl]-benzoate (2), were isolated from the flowers of Pieris formosa. Their structures were determined on the basis of spectroscopic analysis and chemical methods.