21,1 Perkins: Drugs for the Treatment of Leprosy 3 
The acids of this series are found nowhere else in nature, nor 
have they been synthesized in the laboratory. Expressed in 
terms of molecular structure, the distinguishing characteristic 
of these acids is that they contain a closed ring of. five carbon 
atoms. All other known fatty acids have their carbon atoms 
in the form of an open chain. Due to this structural peculiarity, 
the acids of the chaulmoogric series have the power of optical 
rotation, and may be detected by the polariscope. 
The nomenclature of the peculiar acids of chaulmoogra oil was 
initiated in 1879 by Moss,° who supposed chaulmoogra oil to 
be derived from Gynocardia odorata. He gave the name “gyno- 
cardic acid” to a crystalline preparation melting at about 29° 
C. This was later shown to be mixture, by Power and his 
collaborators,’° who definitely isolated from chaulmoogra oil the 
acids which they named chaulmoogric and hydnocarpic. They 
considered the glyceryl esters of these acids, together with some 
palmitic, to be the chief constituents, of chaulmoogra oil. 
The fact that some Hydnocarpus oils are very similar to Ta- 
raktogenos oil has led to the claim that these may be legiti- 
mately sold as chaulmoogra oil. If the word chaulmoogra is 
to be defined by its original native meaning, this claim can 
hardly be denied; but the modern practice of standardizing 
medical terms necessitates the restriction of the word to Ta- 
raktogenos kurzii. The question of the medicinal value of the 
various Hydnocarpus oils must be decided on their own merits. 
Chemical investigation has shown that they are very similar 
to chaulmoogra oil and contain at least two of the same peculiar 
fatty acids which have been proved to be effective in the treat- 
ment of leprosy. The optical rotatory power is the best present 
single analytical criterion of this property, though the results 
of McDonald and Dean“ indicate that the iodine absorption | 
value is also important. The writer expects to publish an 
analytical study of various Hydnocarpus oils in the near future. 
The clinical results on record are not confined to chaulmoogra 
oil; in fact, experts in India have in recent years preferred 
Hydnocarpus wightiana oil. This is encouraging to us in the 
Philippines, as we have no indigenous Taraktogenos kurzit, but 
®* Moss, Year-book of Pharmacy (1879) 523-533. 
” Power and Gornall, Journ. Chem., Soc. 85 (1904) 838, 851; Power and 
Less, ibid. 87 (1905) 349; Power and Barrowcliff, ibid. 884; Barrowcliff 
and Power, F. B., Am. Journ. Pharm. 87 (1915) 493. 
™ McDonald, J. T., and Dean, A. L., Journ. Am. Med. Assoc. 76 (1921) 
1472. 
