With urea derivatives

Interaction of iV-pentafluorophenylcarbonimidoyl dichloride with benzonitrile and aluminium trichloride leads to l-pentafluorophenyl-4,6-diphenyl-13 -triazin-2-one along with urea derivatives . Reaction of perfluoro-5-azanon-4-ene with a range of bidentate nitrogen nucleophiles (urea, substituted amidine hydrochlorides and guanidine), in the presence of triethylamine or potassium hydroxide, effectively provides fluorinated 1,3,5-triazines 16-19 <00JFC(103)105>. 

Barbiturates are derivatives of barbituric acid and are synthesized by condensation of malonic acid derivatives with urea derivatives. 

Perchloro-lA3,3A3-diphosphetane 48 reacts with urea derivative 60 to form tricyclic species 61, which can be rearranged to the symmetric isomer 62 <2002ZFA1903>. 

A novel l,4,6-oxadiazocine-2,5,8-trione 154 was obtained by the condensation of glyoxylic acid with urea derivatives under acidic catalysis conditions (Equation 32 <1997JHC829>). 

Enantiomerically pure oc-amino acids were prepared in excellent yields via Pd-catalyzed amidocarbonylations using PdBr /PPh, and superior catalyst productivities were achieved (TON = 250,000) [206, 207]. The Pd-catalyzed carbonylation of aldehydes with urea derivatives provided a remarkably simple method for the preparation of 5-,3,5- and... 

Aldonoyl acetic esters (982), obtained from aldehydo- v gSLV derivatives such as 981 and diazoacetic ester, condensed with urea derivatives to give the corresponding 4-(alditol-l-yl)pyrimidines 983 [79MI9 84AQ(C)45] (Scheme 284),... 

Further, the reaction of 3-aryl-l,2,4-triazin-5-ones 34 with urea derivatives affords N-adducts 64 at C-6 of the 1,2,4-triazine ring (Scheme 31) <2003RGB2161>, while on heating of 6-aryl-l,2,4-triazin-3-ones 65 with an excess of cycloalkylimines the N-addition of nucleophiles takes place at C-5 to give the corresponding 5-amino-6-aryl-4,5-dihydro-l,2,4-triazin-3-ones 66 (Scheme 31) <2000RJ0602>. 

MA -Diethylaminomethylene-1,1,1,5,5,5-hexafluoroacetylacetone was shown to react with urea derivatives to afford pyrimidines of type 54, 55, and 56 (93TL(34)7737. ... 

Bromophenols coupled with pyroglutamic acid, deoxygua-nosine, with urea derivatives and with nucleosides, as well as brominated derivatives of tetrahydroisoquinoline were characterized for the first time in the species Rhodomela confervoides of Chinese origin, harvested aroimd Qingdao (Zhao et al, 2005 Ma et al, 2006, 2007). However, none of these derivatives seems to present any significant antimicrobial or cytotoxic activity. 

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