ORGANIC CHEMISTRY 



203 



HO . CH— NH 



HO . CH CHOH 



\/ 

 NH 



(i) 



CHOH 

 / \ 

 ^NH— CH NH 



HC 



^ N — CH CHOH 



\ / 

 NH 



(ii) 



On these lines it seems that all naturally occurring nitro- 

 genous compounds can be built up. Some evidence of the 

 formation of glyoxaline, pyrrole, and p3Tidine derivatives in 

 the photochemical reaction between formaldehyde and nitrites 

 has been obtained by the authors and other workers, and there 

 is no doubt that the views put forward are very suggestive and 

 open up a large field for further investigation. 



Constitution and Synthesis of Laudanine. — The 'constitution 

 of this member of the group of opium alkaloids has been 

 studied by Spath {Monatsh., 1920, 41, 297, and 1921, 42, 273). 

 Its relation to laudanosine was confirmed by methylation to 

 racemic laudanosine by means of diazomethane. As the 

 constitution of the latter is represented by (iii) the onty problem 



CH 



MeO 



CH2 



I 



NMe 



CH 



CH2- 

 (iii) 



OMe 

 OMe 



NMe 



^" OH 



CH2— ( )OMe 

 (iv) 



which remained was the determination of the position of the 

 unmethylated hydroxyl group. It was known that laudanine 

 on oxidation yielded metahemipinic acid (4 : 5-dimethoxy- 

 phthahc acid), so the hydroxyl group must be in the benzyl 

 residue. By ethylation of this group in order to protect and 

 identify it, followed by oxidation of the product, 4-methoxy — 

 3-ethoxy-benzoic acid was obtained ; laudanine must therefore 

 have the structure (iv). This has now been confirmed by a 

 direct synthesis. 3 -Hydroxy — 4-methoxyphenylactic acid (v), 

 prepared by a long synthesis from isovanillin, was converted 

 to its carbethoxy-derivative and then to the acid chloride (vi), 

 which was condensed in benzene solution with /3-amino ethyl- 

 3 : 4-dimethoxybenzene (vii). The compound so obtained (viii) 



