Cyclic guanidines. I. Synthesis of hypoglycemic 1-substituted 2-imino-1,3-diazacycloalkanes.

N-Cyanoimines in the Synthesis of Heterocyclic Compounds. (Review)

“…The useful characteristics of cyanoimines may find practical applications in medicine. Thus, for example, the cyanoimines 18 exhibited hypoglycemic activity [18]. The cyanoimines 14 have good electronaccepting characteristics [11].…”

“…When heated with hydrobromic acid, the N-cyanoimine 25 undergoes cyclization to 5-amino-7-bromo-4-methyl-3,4-dihydropyrido[2,3-d]pyrimidin-2(1H)-one 38 [21]. Compounds 18 and 19 are hydrolyzed similarly [18]. The useful characteristics of cyanoimines may find practical applications in medicine.…”

“…Thus, for example, 2-cyanoiminoimidazolidines 18 (n = 1) and 2-cyanoimino-1,3-diazines 19 (n = 2) were obtained with good yields by heating dimethyl N-cyanodithiocarbonimidates with diamines (100-200°C, 15 min) [18]. A solution of dipotassium N-cyanodithiocarbonimidate in aqueous acetone reacts with 1,2-dibromoethane and 1,3-dibromopropane at room temperature to form the corresponding 2-cyanoiminodithiolane 20 and 2-cyanoimino-1,3-dithiane 21 [19].…”

Synthesis of azoles and azines and their condensed derivatives based on N-cyano-S-alkylthioureas (Review)

“…In the case of aliphatic diamines the reaction does not stop at the formation of the intermediate isothioureas, since the second amino group then undergoes aminolysis, leading to good yields of 2-cyanoiminoimidazolidine 19 or 2-cyanoimino-1,3-diazine 20 [24]. (21) is obtained by boiling N-cyano-S-alkylisothioureas 1 with 1,1-dimethyl-2,2-pentamethyleneaziridinium perchlorate in dioxane for 3-5 h [25].…”

The Application of Microwaves in Combinatorial and High‐Throughput Synthesis as New Synthetic Procedure in Drug Discovery

“…The obtained compounds can be easily reacted with alkyl halides to isolate isothioureas 18 ± 25 as final step (Table 1) The general approach to cyclic guanidine 27 is instead the reaction of a diamine 26 with cyanogens bromide [30] that requires long times [31]. Heating the reaction mixture in the microwave afford the guanidines, as shown in Scheme 7, in good yields (53 ± 61%) in just 10 min.…”