pyran,

communication 5. ritter reactions in the pyran series
βdglucopyranosiduronicacid4nitrophenyl
cyclopenta[c]pyran-1-ol, octahydro-4,7-dimethyl-结构式图片|75281
2hpyrantetrahydroheptadecahydrate635721425
3-chloro-pyran-2-one