(S)-(-4,4,4-TRIFLUORO-3-(INDOLE-3-)BUTYRIC ACID, A NOVEL FLUORINATED PLANT-GROWTH REGULATOR())

Racemic 4,4,4-trifluoro-3-(indole-3-) butyric acid (TFIBA) has been sy nthesized and shown to inhibit Avena coleoptile elongation. (S)-(+)-TF IBA (fig. 1), which was prepared by an enzymatic method and markedly p romotes root growth of Chinese cabbage, lettuce and rice plants, is a novel fluorinated plant growth regulator. Activity of the (S)-(+)-enan tiomer of TFIBA was 10-fold greater than that of the (R)-(-)-enantiome r in the first two plant species and 5-fold greater in rice.