146374-56-3

Usage

InChI:InChI=1/C13H12Cl2N4O2/c1-2-21-11(20)6-19-5-8-10(18-13(19)17-7-16)4-3-9(14)12(8)15/h3-4H,2,5-6H2,1H3,(H,17,18)

Upstream product

• 70406-92-7 N-(6-amino-2,3-dichlorobenzyl)glycine ethyl ester 
• 10191-60-3 dimethyl N-cyanodithioiminocarbonate 
• 200571-09-1 S-methyl-N-cyano-N'-(2-amino-5,6-dichlorobenzyl)isothiourea 
• 79463-77-7 N-cyanodiphenylcarbonimidate 
• 24771-25-3 dimethyl (N-cyanoimido)carbonate 
• 31350-31-9 bis(benzylmercapto)methylene cyanamide 
• 105-36-2 ethyl bromoacetate 
• 200571-11-5 2-cyanoimino-5,6-dichloro-1,2,3,4-tetrahydroquinazoline 

Downstream Products

• 68475-42-3 anagrelide 

Relevant academic research and scientific papers

Process for the preparation of 6,7-dichloro-1,5-dihydroimidazo[2,1-b]quinazolin-2[3H]-one

This invention relates to a new and improved process for the preparation of 6,7-dichloro-1,5-dihydroimidazo[2,1-b]-quinazolin-2[3H]-one of formula STR1 (anagrelide), a valuable blood platelet antiaggregative compound. According to the process of the invention the compound of formula (I) is prepared by subjecting a new 2-cyanoiminoquinazoline derivative of the general formula STR2 wherein R stands for cyano or a group of the formula COOR1, in the latter R1 representing lower alkyl optionally carrying a phenyl substituent, to thermal cyclization in an acidic medium. The invention also relates to new 2-cyanoiminoquinazo-lines of the general formula (III) used for the production of anagrelide and to the preparation of the said compounds. The invention provides an advantageous process for the preparation of anagrelide which is devoid of the drawbacks of the hitherto known processes and renders possible the production of the compound of the formula (I) on industrial scale, too.

Process for and 2-(cyanoimino)-quinazoline derivatives useful as intermediates in the preparation of 6,7-di-(chloro)-1,5-di(hydro)-imidazo-[2,1-b]quinazolin-2[3H]-one and process for preparing the 2-(cyanoimino)-quinazoline derivatives

A subject matter of the invention is a process for the preparation of 6,7-di-(chloro)-1,5-di-(hydro)-imidazo[2,1-b]quinazolin-2[3H]-one of formula or a salt thereof including their hydrates, characterized by subjecting [2-(cyanoimino)-5,6-di-(chloro)-1,2,3,4-tetra-(hydro)-quinazolin-3-yl]-acetonitrile or a /2-(cyanoimino)-5,6-di-(chloro)-1,2,3,4-tetra-(hydro)-quinazolin-3-yl/-acetic acid alkylester of the general formula wherein R'stands for a cyano group or a group of the formula in which latter R1represents a straight or branched alkyl group having from 1 to 6 carbon atom(s), optionally carrying a phenyl substituent, to thermic cyclization in an acidic medium. Further subject matters of the invention are [2-(cyanoimino)-5,6-di-(chloro)-1,2,3,4-tetra-(hydro)-quinazolin-3-yl]-acetonitriles or -acetic acid alkylesters of the general formula wherein R' is as defined above, useful as intermediates in the said process and a process for preparing them.