Furfural

Furfural has a characteristic penetrating odor typical of cyclic aldehydes. 

Furfural is prepared industrially from pentosans that are contained in cereal straws and brans; these materials are previously digested with diluted H2S04, and the formed furfural steam is distilled.

Furfural can be used as solvent, resins, and other organic materials; as insecticide, fungicide, germicide; an intermediate for tetrahydrofuran, furfural alcohol, phenolic and furan polymers.