2 P-AMINOBENZOIC ACID 



Page 



D. Therapeutic Uses 59 



1. Gray Hair 59 



2. Dermatology 60 



3. Rickettsial Diseases 60 



4. Neoplastic Diseases 61 



5. Other Diseases 61 



XII. Detoxication of Arsenicals 62 



XIII. Sulfonamide Reversal 66 



XIV. Therapeutic Activity 79 



A. Rickettsial Diseases 79 



B. Rheumatoid Diseases 81 



C. Achromotrichia 83 



D. Thyrotoxicosis 84 



E. Miscellaneous Diseases 85 



I. Nomenclature 



ROBERT S. HARRIS 



Accepted name: p-Aminobenzoic acid 



Obsolete names: Vitamin B^ Anti-gray hair factor 



Bx factor Trichochromogenic factor 



Chromotrichia factor Bacterial growth factor P 



Anticanitic vitamin 



Bacterial vitamin H 

 Empirical formula: C7H7NO2 

 Chemical name: 4-Aminobenzoic acid 

 Structure : 



HoN— <r ^— COOH 



■<3 



II. Chemistry 



LEMUEL D. WRIGHT and PETER A. TAVORMINA 



A. PREPARATION 



Both reductive and oxidative methods have been used in the synthesis 

 of p-aminobenzoic acid (PABA). 



The chemical reduction of p-nitrobenzoic acid has been effected with 

 ammonium sulfide/ tin and hydrochloric acid,--^ ferrous sulfate and am- 



1 G. Fischer, Ann. 127, 137 (1863). 



2 J. Wilbrand and F. Beilstein, Ann. 128, 257 (1863). 



3 E. Widnmann, Ann. 193, 202 (1878). 



