Notes on scientific research. 141 



The action of homopiperonylic acid on homopiperonylamine produces homo- 

 piperonoylhomopiperonoylamine. The coupling of this amide to an iso-quinolinederivate 

 shapes itself just in the same, manner as with formylhomopiperonylamine, whereby 

 piperonylnorhydrastinin results from which one can obtain by methylation and sub- 

 sequent reduction a tetrahydro-iso-quinoline derivate, the latter forming hydrastinine and 

 piperonyl on being oxidised, which can be employed again for a repetition of the 

 operation. 



Homopiperonoylhomopiperonylamine can also be manufactured from piperonal and 

 hippuric acid, whereby the formation of homopiperonylamine is avoided 1 ). 



Homologous products of hydrastinine can also be prepared with the aid of piperonal 

 derivates 2 ). 



For instance by treating benzenehomopiperonylamine with fairly strong hydrochloric 

 acid the hydrochloride of i-phenylnorhydrohydrastinine is formed. One can obtain this 

 compound also by boiling the benzene derivative with benzene and phosphorus oxy- 

 chloride, and equally so by reduction with phenylnorhydrastinine. 



For the purpose of preparing i-methylworhydrohydrastinine, homopiperonylamine 

 is heated on the water-bath with acetic aldehyde solution and the resulting compound, 

 dissolved in benzene, treated with hydrochloric acid gas. 



Cinnamaldehyde and homopiperonylamine react in producing cinnamylidene 

 norhydrohydrastinine ; cinnamylidenehomopiperonylamine which is formed thereby is 

 rearranged in the same manner as the above-mentioned acetic aldehyde compound. 



i-Methylenedihydroxyphenylnorhydrohydrastinine is an oil which can also be 

 obtained in crystals. For this purpose, piperonal and piperonylamine in alcohol are 

 heated and one then rearranges the resultant Schiff base by heating it with phosphorus 

 oxychloride in a solution of toluene. 



Homologous hydrastinines which are combined with other alkyls instead of with 

 methyl at the nitrogen atom can be obtained by adding alkylhaloids to norhydrastinine 3 ), 

 identical or analogous compounds by means of internal coupling of alkylacylhomo- 

 piperonylamines. The position 1 of these hydrastinines is substituted if, instead of 

 starting from formyl-, one proceeds from other acylhomopiperonylamines. In this 

 manner one obtains bases which produce vascular distensions just like hydrastinine 4 ). 



Thus n-ethylnorhydrastinine can be produced by preparing ethylhomopiperonyl- 

 amine via the benzoate, then by heating the former with the calculated quantity of 

 formic acid, and by coupling the formyl compound to the isoquinoline derivate by 

 boiling the latter in a solution of benzene with phosphorus oxychloride. 



For the purpose of manufacturing i-phenylhydrastinine, methylhomopiperonylamine 

 is heated with benzoic anhydride and the resulting benzoyl compound boiled in the 

 usual manner with toluene and phosphorus oxychloride. Or one can also transform 

 homopiperonylamine by the aid of benzoylchloride into the benzoyl compound and 

 boil the latter with toluene and phosphorus oxychloride, whereby i-phenylnorhydrastinine 

 is formed, combines with methyl iodide, forming i-phenylhydrastinine iodide. 



i-Methylhydrastinine can in like manner be obtained from homopiperonylamine 

 by boiling its acetate, dissolved in toluene, with phosphorus pentoxide. The 2-methyl- 

 norhydrastinine thus produced is transformed into i-methylhydrastinine by means of 

 methyl iodide. 



*) W. Kropp, H. Decker and C Zoellner; Berl. Berichte 42 (1909), 1184. — *) H. Decker and P. Becker, 

 IAehigs Annalen 395 (1913), 342; B. R. P. 257 138; Chcm. Zentralbl. 1912, I. 1154. — s ) H. Decker and P. Becker, 

 tdeUgs Annalen 395 (1913), 325. — D. R. P. 267699; Chem. Zentralbl. 1914, I. 201. — *) H. Decker, LieMgs Annalen 

 395 (1913) 282. — B. R. P. 235358; Chem. Zentralbl. 1911, II. 171. 



