Claims
- 1. A process for preparing a urea derivative which comprises reacting a primary phenyl carbamate or phenyl thiocarbamate with ammonia, a primary amine, or secondary amine, in dimethyl sulfoxide solution to give the corresponding urea derivative.
- 2. The process as claimed in claim 1 which comprises reacting the carbamate derivative of the formula 1: ##STR51## wherein X is oxo or thioxo and R.sub.1 is lower alkyl, a monosubstituted or disubstituted lower alkyl wherein the substituent is selected from the group consisting of lower alkoxycarbonyl and phenyl; 4-{1-(phenylmethyl)piperidinyl}, phenyl or phenyl monosubstituted with a substituent selected from the group consisting of lower alkoxy, lower alkoxycarbonyl, cyano, lower alkanoyl and (lower alkoxycarbonyl)-(lower alkyl); 4-(2-amino-4-thiazoyl)phenyl or 4-{2-{{(1,1-dimethylethoxy)carbonyl}amino}-4-thiazolyl}phenyl with an amine of the formula Q:
- HNR.sub.2 R.sub.3 (Q)
- wherein R.sub.2 is hydrogen or lower alkyl and R.sub.3 is hydrogen, lower alkyl, lower alkyl monosubstituted with phenyl or 2-pyridinyl; phenyl or 4-{1-(phenylmethyl)piperidinyl}; or R.sub.2 and R.sub.3 together with the nitrogen to which they are attached form a ring selected from the group consisting of ##STR52## to obtain the corresponding urea derivative of formula 2: ##STR53## wherein X, R.sub.1, R.sub.2 and R.sub.3 are as defined in this claim.
- 3. The process as claimed in claim 1 wherein the molar ratio of the phenyl carbamate or phenyl thiocarbamate to ammonia or to the primary or secondary amine ranges from 1:1 to 1:1.1.
- 4. The process as claimed in claim 1 wherein the reaction time ranges from instantaneously to three hours and the reaction temperature ranges from 22 to 100.degree. C.
- 5. The process of claim 1 wherein the urea derivative is N'-{4-{(2-{{(1,1-dimethylethoxy)carbonyl}amino}-4-thiazolyl}phenyl}-N-{2-(2-pyridinylethyl}urea, the primary phenylcarbamate is phenyl N-{4-{2-{{(1,1-dimethylethoxy)carbonyl}amino}-4-thiazolyl}phenyl}carbamate and the amine is N-methyl-N-{2-(2-pyridinyl)ethyl}amine.
- 6. The process of claim 1 wherein the urea derivative is N'-{4-(2-amino-4-thiazolyl)phenyl}-N,N-dibutylurea, the primary phenylcarbamate is phenyl N-{4-(2-amino)-4-thiazolyl)phenyl}carbamate and the secondary amine is N,N-dibutylamine.
Parent Case Info
This application is a continuation of provisional application No. 60/026,202, filed Sep. 17, 1996.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3161676 |
Adams |
Dec 1964 |
|
5420164 |
Mishina et al. |
May 1995 |
|