1930 



770 



XlTRO-6-METHYLHYD.VNTOlN 

 N(NO,).CH, 



^^^Me .CO 



Harries, C. und Weiss, M. Liebiss 

 Ann. Chein., Leipzig, 327, 1903, r.355- 

 384). 



CYCLOID CsHeON; 



Dimethylpaxabanic acid 



NMe . CO 

 ^'0<KMe.CO 

 Behrend, R. und Fricke, T.. Liebigs 

 Ann. Chem., Leipzig, 327, 1903, (253-- 

 268). 



CYCLOID C5H.O2N, 



Metliyldiketopiperazine 



XH,.C<) , 

 -CO .CHMe- 



NH<!^"^!^;;,r.>NH 



Fischer, E. und Otto, E. Berlin, Bar. 

 D. chem. (ies., 36, 1903. (2106-2116, 

 2993). 



CYCLOIDS CiHiOiNs 



f-Ethyl-hydantoin 



NH . CH2 

 C^<XEt.CO 

 and the niteo derivative 

 X(N02) . CH2 



C0< 



NEt . CO 



Harries, C. imd Weiss, M. Liebigs 

 Ann. Chem., Leipzig, 327, 1903, (355- 

 384). 



5, 5-Dimethylhydantoin 



llIIN'O DERIV.VTIVE p x-TTX \-TJ 



Piloty, 0. und Vogel, W. Berlin, 

 Ber. D. chem. Ges., 36, 19u3, (^1283- 

 1304). 



CYCLOID C5H3O3N2 



Imino derivative C5H9O2N3 i.e. 

 cue, •N(0H) 

 C(NH).KH ^ 



Piloty, 0. und Vogel, W. Berlin, Ber. 

 D. chem. Ues., 36, 1903, (1283-1304). 



1930 



Porphyrexine 



Cil_2 -^lOH) 

 C(NH).NH ^ 

 (2, i-DUmino-'i-oxjj-p, 5-dimethyl- 

 hydantoin) 

 and its chloro derivative. 

 PUoty, 0. und Vogel, W. Berlin, Ber. 

 D. chem. Ges., 36, 1903, (1283-1304). 



CYCLOID C6H4O4N2 



4, 5-Pyridazine dicarboxylic acid 



N . CH : C . CO2H 

 N . CH : C . CO2H 

 Gabriel, S. Berlin, Ber. D. chem. 

 Ges., 36. 1903, (3373-3378). 



CYCLOID CeH.0N2 



4.Methyl-3-acetyl-pyrazole 



CAc . CMe 

 ^NH .CH 

 and its phenylhydrazone. 

 Klages, A. und Ronneburg, A. Ber- 

 lin, Ber. D. chem. Ges., 36, 1903, (1128- 

 1132). 



CYCLOID CeH,03N2 



Oxy- /3 - dimethyluracil 



Behrend, R. und Fricke, L. Liebigs 

 Ann. Chem., Leipzig. 327, 1903, (253- 



* 



I 



CYCLOID C7H6O4N2 



Dicarboxyglutaric diimide 



>^-H<gS:CH>Cl_^C0>^^^ 

 Guthzeit, Max und Jahn, Carl. J. 

 prakt. Chem., Leipzig, (N.F.), 66, 1902, 

 (1-15). 



CYCLOID CjHsO'N, 



Dimethylpyridazine carboxylic acid 



Ethyl ester. 

 Paal, C. und Ubber, Jean. Berlin, 

 Ber. D. chem. Ges., 36, 1903, (497- 

 512). 



