J. Soc. Cosmetic Chemists, 19, 141-148 (Mar. 4, 1968) The Function of Bandrowski' Base in Hair Dyeing MOSES ALTMAN, B.S., and MARTIN M. RIEGER, Ph.D.* Presented September 21, 1967, Seminar, Chicago Synopsis--Proposals for the structure of Bandrowski's Base (BB) are reviewed, and it is concluded that the structure originally proposed by Green is the correct one. The role of BB in dyeing of human hair was studied by examining hair dyed with p-phenylenediamine and hydrogen peroxide. Solvent extraction of dyed hair or decomposition by dilute alkali yielded mixtures which contained little or no BB when they were examined by thin-layer chromatography. Based on these experiments, it is concluded that BB is not the main colorant of hair dyed with p-phenylenediamine. INTRODUCTION Bandrowski's Base (BB) has been the subject of considerable controversy since its discovery in 1889 (1). Its exact structure and its role in hair and fur dyeing by oxidation of p-phenylenediamine (PPD) have been vigorously debated (1-11). It is the purpose of this study to review the evidence for a definitive structure of BB and to investigate BB's role in the in vivo dyeing of hair. STRUCTURE Essentially two structures have been proposed for BB. One of these (I) was proposed without any evidence by Bandrowski (1) and has sub- sequently received the support of other workers (4, 7). A second struc- ture (II) has been proposed by Green (6) and was corroborated experi- mentally by Sunde and Lauer (8, 9). Finally, a third structure has been * Warner-Lambert Research Institute, 170 Tabor Rd., Morris Plains, N.J. 07950. 141

142 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS proposed by Austin (10). This structure (III) is tautomeric with II, and the differences between structures II and III appear to be of second- ary interest. NH2 NHz NH2 NH2 NH2 NH2 NH NH Green's (6) evidence for structure II was largely conjectural and is based on his work on the structure of Barsilowsky's Base (oxidation product of p-toluidine). The evidence of Sunde and Lauer (8, 9) was negative these workers synthesized I and found it to be different from BB. During the course of the studies reported below, Greenough and Altman (11) of this laboratory chose one of the modern techniques of structural organic chemistry to obtain a more definitive answer to this problem. Their nuclear magnetic resonance data clearly indicate that structure II is the correct one. The evidence presented by Green and later by Sunde and Lauer is, therefore, confirmed. ROLE OF BANDROWSKI'S BASE IN HAIR DYEING The formation of BB by oxidation of PPD in the presence of hydrogen peroxide is well established. It is generally assumed that the inter- mediate in the formation of BB is quirtone diimine. It is also generally assumed that BB via some unknown mechanism is further oxidized or modified to an azine-like compound (12-18). It has even been claimed that this azine complexes or reacts further with hair keratin (19). Cox (13, 16) indicated that BB is formed during dyeing of keratin fibers. He further believed that the color body is an azine formed