Synthesis of 5-(aminomethylidene)imidazol-4-ones by using N , N -dialkylformamide acetals
- PDF / 213,182 Bytes
- 3 Pages / 594 x 792 pts Page_size
- 2 Downloads / 193 Views
Synthesis of 5-(aminomethylidene)imidazol-4-ones by using N,N-dialkylformamide acetals Elvira R. Zaitseva1,2, Alexander Yu. Smirnov2*, Igor A. Ivanov2, Konstantin S. Mineev2, Mikhail S. Baranov2,3 1
D. Mendeleev University of Chemical Technology of Russia, 9 Miusskaya Sq., Moscow 125047, Russia 2 Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 16/10 Miklukho-Maklaya St., Moscow 117997, Russia 3 N. I. Pirogov Russian National Research Medical University, 1 Ostrovityanova St., Moscow 117997, Russia; е-mail: [email protected]
Submitted April 7, 2020 Accepted after revision August 4, 2020
Translated from Khimiya Geterotsiklicheskikh Soedinenii, 2020, 56(8), 1097–1099
We have developed a simple methodology for the synthesis of various 5-(aminomethylidene)imidazol-4-ones by condensation reactions of imidazol-4-one that was prepared in situ and acetals of N,N-dialkylformamides. Keywords: 5-(aminomethylidene)imidazolones, formamide acetals, imidazolones, GFP chromophore.
Acetals of formamides (formamide acetals) are stable and readily available synthetic equivalents of formamides – compounds that often serve as important synthetic intermediates.1 A common application of these compounds is in the synthesis of enamine-type compounds, while only rare examples are known for their role in the synthesis of heterocyclic compounds.2–4 During our research aimed at expanding the list of known analogs of the green fluorescent protein (GFP) chromophore (benzylideneimidazolone analogs) and characterization of their optical properties, we established that their enamine analogs – 5-(aminomethylidene)imidazol-4-ones – remain practically unknown in the literature (Fig. 1).5 We were able to successfully synthesize a series of similar compounds by using imidates,6 but the yields of these transformations were found to be very low. For that reason, a search was continued for effective approaches to their synthesis. We have previously demonstrated that such compounds can interact with boron trifluoride, leading to the formation of fluorescent derivatives.6 It is likely that they can also be used as fluorescent sensors for the detection of metal ions. Furthermore, the structurally related indolinones exhibit antimalarial activity,7 which 0009-3122/20/56(8)-1097©2020 Springer Science+Business Media, LLC
also motivates the interest of researchers toward the preparation of similar compounds. During the current work, we accomplished the synthesis of 5-(aminomethylidene)imidazol-4-ones 4a–f by first converting amidophosphazene 16 into imidazolones 2a,b, which were used in situ for subsequent condensation with formamide acetals 3a–e. The synthesis was performed according to the following procedure: 2-alkyl-3-methyl-3,5dihydro-4H-imidazol-4-ones 2a,b were obtained as a result of a reaction between triphenylphosphanylidene derivative of glycine N-methylamide 1 and an aliphatic acid
Figure 1. The structures of 5-(benzylidene)imidazol-4-ones and 5-(aminomethylidene)imidazol-4-ones.
1097
Chemistry of Heterocycl
Data Loading...
