Cyclisierung von N‐Acylalanin‐ und N‐Acylglycinestern

Abstract

Cyclization of N‐Acylalanine and N‐Acylglycine Esters The cyclization of N‐(2,6‐Dialkylphenyl)‐N‐acylalanine and ‐glycine esters 1 to 2,4‐pyrrolidinediones 2 or the enols 3 is described. The acylation of 3 gives O‐acyl derivatives; the alkylation of 3 yields mixtures of O‐ and C‐alkylation products.

Synthesis of 1,2,4,5‐Tetrasubstituted Imidazoles Using Sulfuric Acid ([3‐(3‐Silicapropyl)sulfanyl]propyl]ester as a Recyclable Solid Acid

“…The members of this class of compounds are known to possess NO synthase inhibition and antifungal, antimycotic, antibiotic, antiulcerative, antibacterial, antitumor, and CB1 receptor antagonistic activities . Various substituted imidazoles act as inhibitors of p38 MAP kinase [4a] and B‐Raf kinase [4b], glucagon receptors , plant growth regulators , therapeutic agents , and pesticides .…”

Click Synthesis of Novel 3‐(2‐(2,4,5‐Triphenyl‐1H‐imidazol‐1‐yl)ethyl)‐1H‐indoles Catalyzed by Glacial Acetic Acid and their Antibacterial Evaluation

“…Compounds containing imidazole backbone possess versatile biological activities like anticancer, [6] antibacterial, [7] antifungal, [8] antiinflammatory, [9] antitumor, [10] properties. Also, the imidazole nucleus is present as an essential structure in a number of therapeutic agents, fungicides, herbicides, [11] plant‐growth regulators, [12] inhibitors of p38 MAP kinase, [13] and potent inhibitors of protein‐protein interactions [14] …”

“…[4,5] Compounds containing imidazole backbone possess versatile biological activities like anticancer, [6] antibacterial, [7] antifungal, [8] antiinflammatory, [9] antitumor, [10] properties. Also, the imidazole nucleus is present as an essential structure in a number of therapeutic agents, fungicides, herbicides, [11] plant-growth regulators, [12] inhibitors of p38 MAP kinase, [13] and potent inhibitors of protein-protein interactions. [14] There are numerous methods reported for the synthesis of 1,2,4,5-tetrasubstituted imidazoles by four-component condensation of benzil with a variety of substituted aldehydes, primary amines and ammonium acetate using different catalysts such as sulphated yttria (SO 4 /Y 2 O 3 ), [15] L-Proline, [16] L-Cystein, [17] MCM-41, [18] p-TSA, [19] CAN, [20] Molecular Iodine, [21] Bronsted Acid Ionic Liquid, [22] DABCO, [23] Y(NO 3 ) × 6H 2 O, [24] (CuNO 3 ) 2 -Zeolite, [25] BF 3 ⋅ SiO 2, [26] Silica gel/NaHSO 4, [27] HCIO 4 -SiO 2, [28] ZrCl 4, [29] InCl 3 ⋅ 3H 2 O, [30] [31] Silica Sulphuric acid, [32] NiCl 2 ⋅ 6H 2 O/Al 2 O 3, [33] Yb(OTf) 3, [34] Selectflour TM , [35] H 2 SO 4 ⋅ SiO 2, [36] Ultrasonic Irradiation, [37] Amberlyst A-15, [38] PEG-400, [39] Glycerol, [40] and AcOH.…”

“…, entries[12][13][14][15][16]. Among these solvents, methanol gave excellent yield (98 %) of the target product within one minute.…”

Hydrogen bonding framework in imidazole derivatives: Crystal structure and Hirshfeld surface analysis

“…They are also known as melanocortin-4-receptor (MC4-R) antagonists [12], inhibitors of P38MAP kinase [13], herbicides [14] and plant growth regulators [15]. Besides their biological and pharmacological activities they also act as dyestuff catalysts, polymerizing agent [16,17] and also photo sensitizers in photography [18,19]. The potency and wide applicability of the imidazole pharmacophore can be attributed to its hydrogen bond donor-acceptor capability [20].…”