Process of preparing 1,3-bis(2-chloroethyl)-1- nitrosourea
CA 1082223 A · Owner: United States Of America (Government Of The) United States Department Of Energy · Inventors: Yanko, William H.; Sharp, Donald E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of producing 1,3-bis(2-chloroethyl)-1nitrosourea (BCNU) by nitrosation of 1,3-bis(2-chloroethyl)urea utilizing as a nitrosating agent dinitrogen trioxide (N203) in molar excess of theoretical wherein the molar excess of N203 ranges from 10-200% and preferably from 10-20%. The nitrosation reaction is conventionally carried out in the cold From 0°C to -20°C and a non-aqueous solvent is utilized. The preferred non-aqueous solvent is of the chlorinated variety; i.e. methylene dichloride. Other preferred solvents include related halogenated compounds such as ethylene dichloride nitro-compounds such as nitromethane, acetonitrile and simple, ethers such as ethyl ether. Other less …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted July 22, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 22, 1997.
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Timeline
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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.