STEREO-CHEMISTRY AND PHYSIOLOGY 463 



atropine, which is the corresponding racemic form. These 

 substances are the tropine esters of tropic acid, and have 

 the formula : 



CH.,OH CH, CH CH., 



I I " I 



C 6 H 5 -CH-CO-0-CH N-CH a 



CH., CH CHo 



It was found that both atropine and /-hyoscyamine have the 

 same action upon the central nervous system of animals, the 

 effects being not only qualitatively but also quantitively identical. 

 When applied to the spinal cord reflexes, atropine has a more 

 powerful influence than the active isomer ; but this is reversed 

 in the case of the nerve ends of the heart, the salivary glands, or 

 the pupil of the eye ; for at each of these points /-hyoscyamine 

 has an effect twice as strong as that produced by atropine. 

 From these results we can deduce the probable effect of dextro 

 hyoscyamine. We know that ^/-hyoscyamine (atropine) has 

 the same effect as /-hyoscyamine on the central nerve system 

 of mammals ; therefore in this case dextro and lsevo forms must 

 have the same effect. But, on the other hand, ^/-hyoscyamine 

 has a greater effect than /-hyoscyamine on the spinal cord, 

 so that here, obviously, <f-hyoscyamine must exert a greater 

 influence than /-hyoscyamine. In the case of the heart, the 

 effects are again reversed ; for since here /-hyoscyamine is 

 twice as powerful as ^/-hyoscyamine, it appears that ^-hyos- 

 cyamine must be almost without action. Of course this reason- 

 ing assumes that the racemic compound breaks up into the 

 two antipodes before it acts upon the various nerves. 



Two other substances should now be described, as they are 

 closely allied to the tropine group. If in the formula of tropine 

 we replace the radicle — CH 2 — CH 2 — by two methyl groups, and 

 at the same time exchange a hydrogen atom of a — CH — group 

 for a methyl radicle, we obtain the following formula, which 

 represents N-methyl-vinyl-diacetone-alkamine : 



CH 3 



C H 2 C C H 3 



I I 



CH.OH N . CH S 



I I 



CH 2 CH — CH 3 



Like tropine itself, this compound exists in two isomeric forms, 

 the mandelic ester of one being an oil, while that of the other 



