480 



C. A. West 



^"^ 



(I) 



(2) 



(3) 



Structure 3 would seem less likely since bean factor II does not fluo- 

 resce when dissolved in sulfuric acid, whereas A3, with a double bond 

 in the A-ring, does. 



There is no evidence to assist in the placement of a lactone, a 

 carboxylic acid, or an alcoholic hydroxyl, although it would seem 

 most likely they would be substituted in one of the positions occupied 

 by such groups in Aj, Ao, A3, or A4.^ 



SUMMARY 



Two crystalline substances, with gibberellin-like biological pro- 

 perties, called bean factor I and bean factor II, have been isolated 

 from acetone-water extracts of immature seed of PJiaseolus vulgaris. 

 The infrared spectrum and other properties of bean factor I dem- 

 onstrate that it is identical with gibberellin A^ isolated from the 

 fungus Gibberella fiijikiiroi. The biological and chemical properties 

 of bean factor II show that it is not identical with the fungal gibber- 

 ellins, Aj, A2, A3, or A4. It has a carboxylic acid group and a neutral 

 equivalent of approximately 360. Evidence is also presented for the 



* After the preparation of this manuscript the author was supplied with a 

 copy of a report to he published by J. Mac\lillan, J. C. Scaton, and P. J. Suter 

 in which they describe the isohition of a substance (gibberellin A^,) from seed of 

 Pliaseolus miiltiflnrus. They assign to this compoiuid the structure: 



COOH 



A comparison of the infrared spectrum of this substance with that of bean factor 

 II shows them to be identical. 



