Online Encyclopedia

Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.

HZN

Online Encyclopedia
Originally appearing in Volume V22, Page 665 of the 1911 Encyclopedia Britannica.
» Make a correction to this article.
» Add information or comments to this article.
Spread the word: del.icio.us del.icio.us it!

HZN CN N•C•NH1 N•C NHz N C - N' (I.) (II.) (III.) (IV.) It may also be obtained as follows [E. See also:

Merck, See also:German See also:Patents 158591 (1903); 162336 (1904)1. Dicyandiamide (I.) condenses with cyanacetic ester to See also:form 2-cyanamino-4-amino-6-oxypyrimidine (II.). This yields an isonitroso-derivative which on reduction gives 2-cyanamino-4.5-diamino-6-oxypyrimidine (III.). This See also:compound when boiled with a 90% See also:solution of formic See also:acid gives guanine formate: NH N•C•See also:NH2 N•C•NH2 CN•NH•C - CN•NH•C CH - CN•NH•C C•NH2 N. H2 N:C•OH N.:C•OH (I.) (II.) (III.) It is an amorphous See also:powder, insoluble in See also:water, See also:alcohol and See also:ether, and has both acid and basic properties. Nitrous acid converts it into xanthine. When oxidized by hydrochloric acid and See also:potassium chlorate it yields See also:guanidine, parabanic acid and See also:carbon dioxide. 6-Amino-2-oxypurin, an isomer of guanine, is prepared by See also:heating dichloradenine or 6-amino-2.6.8-trichlorpurin, obtained from 2.6.8 trichlorpurin and See also:ammonia (See also:Fischer, Ber., 1897, 30, p. 2239) with See also:sodium ethylate to 130° C. and reducing the resulting 6-amino-2-ethoxy-8-chlorpurin with hydriodic acid (E. Fischer, Ber., 1897, 30, p. 2245).

6-Amino-8-oxypurin, another isomer of guanine, is prepared by heating 8-oxy-2.6-dichlorpurin with alcoholic ammonia and reducing the resulting amino-oxy-chlor compound with hydriodic acid (E. Fischer, loc. cit.). 7-Methyl guanine is obtained from 7-methyl-6-oxy-2-chlorpurin I in the See also:

decade. The See also:district extend§ from the See also:Ganges See also:north-wards to the frontier of See also:Nepal. It is a level, depressed See also:tract of See also:country, consisting for the most See also:part of a See also:rich, loamy See also:soil of alluvial formation. It is traversed by several See also:rivers flowing from the Himalayas, which afford See also:great advantages of See also:irrigation and water-See also:carriage; in the See also:west the soil is thickly covered with See also:sand deposited by changes in the course of the Kusi. Among other rivers are the Mahananda and the Panar. Under See also:Mahommedan See also:rule See also:Purnea was an outlying See also:province, yielding little See also:revenue and often in a See also:state of anarchy. Its See also:local See also:governor raised a See also:rebellion against Suraj-ud-daula in i 757, after the See also:capture of See also:Calcutta. The See also:principal crops are See also:rice, pulses and oilseeds. The cultivation of See also:indigo is declining, but that of jute is extending. The district is traversed by branches of the Eastern See also:Bengal railway, which join the Bengal and North-Western railway at Katihar.

End of Article: HZN

Additional information and Comments

There are no comments yet for this article.
» Add information or comments to this article.
Please link directly to this article:
Highlight the code below, right click, and select "copy." Then paste it into your website, email, or other HTML.
Site content, images, and layout Copyright © 2006 - Net Industries, worldwide.
Do not copy, download, transfer, or otherwise replicate the site content in whole or in part.

Links to articles and home page are always encouraged.

[back]
HYTHE 		[next]
I00

Site © 2006 - Net Industries