518 
PROFESSOR W. N. HARTLEY ON THE 
The constitution of pipeline. 
According to researches of A. W. Hofmann (Berl. Berichte, vol. 12, p. 984) and of 
Kcenigs {idem, p. 2341) piperine has a constitution somewhat similar to that of 
atropine, that is to say, it is a derivative of a hyclrogenisecl pyridine and of piperic 
acid, which is a benzene derivative, thus:— 
Pyridine. 
Piperidine. 
Piperidine . 
. C 5 H 10 :NH 
N 
H 
Piperic acid 
• C 12 H 10 O 4 
N 
/\ 
Piperine 
• C 17 H 19 N0 3 
HC CH 
HoC CH 3 
II 1 
HC CH 
| | 
HoC CHo 
A/ 
“ \A 
C 
C 
H 
Ho 
Piperic acid has the structure represented by Fittig in the following manner:— 
X CH=CH-CH=CH-CO.OH 
Unlike atropine, piperine shows a very powerful absorption and a persistent 
absorption band extending from wave-length 3600 to 2740. 
The constitution of nicotine. 
According to Wischnegradsky (Ber. 13, p. 2315, 1880), nicotine is an alkyl 
derivative of a di-hydro-pyridine in which the hydrogen united to the nitrogen is 
fC jj 
replaced by ethyl, and the second hydrogen is replaced by allyl, thus :—C 5 HU 3 3 • 
LNC 3 H 5 
The spectrum is quite in accordance with such a constitution, as it yields no 
< 
absorption bands. 
The constitution of atropine. 
The constitution of atropine is that of tropine and tropic acid, less a molecule of 
water, thus :— 
C 5 H 7 (CoH 4 .OH)N.CH 3 Tropine 
C G H 5 .CHj CH3 - OH j . Tropic acid 
6 0 ICO.OH J 1 
C 17 H 23 N0 3 .... Atropine 
According to Ladenburg tropine is probably an ethylene derivative and a hydro- 
