Two new furaldehyde compounds from the rhizomes of Gastrodia elata.

Two new compounds 5-[4'-(4″-hydroxybenzyl)-3'-hydroxybenzyloxymethyl]-furan-2-carbaldehyde (1) and 5-[4'-(4″-hydroxybenzyl)-3'-hydroxybenzyl]-furan-2-carbal-dehyde (2), together with two known 5-(4-hydroxbenzyloxymethyl)-furan-2-carbaldehyde] (3) and 5-(hydroxymethyl)-2-furaldehyde (4), were isolated from the rhizome of Gastrodia elata. Their structures were elucidated by spectroscopic analysis and comparison of their spectral data with those reported previously. All compounds exhibited weak or no cytotoxicity against human colon carcinoma cell line (HT-29) and human chronic myelogenous leukemia cell line (K-562).