奎宁环

2-(四氢-2H-吡喃-4-基)乙酸甲酯

2-(4-甲基四氢-2H-吡喃-4-基)乙酸

Benzyl tetrahydro-2H-pyran-4-ylacetate

1,5-dibromo-3-(2-bromoethyl)pentane