A unified strategy for the synthesis of amorfrutins A and B and evaluation of their cytotoxicity

3,5-Dimethoxy-benzaldehyde was used as a starting material to synthesize a central intermediate, 2-hydroxy-4-methoxy-6-phenethylbenzoic acid that was converted very quickly and with good yields into amorfrutins A and B. Furthermore, this compound was also used as a starting material to synthesize a piperazinyl-rhodamine B conjugate. The latter compound showed good cytotoxicity (EC 50 = 2.3–5.1 mM) and promising selective cytotoxicity (S = 2.1–4.6) for human tumor cell lines as compared to non-malignant fibroblasts (NIH 3T3).