Studies on the interaction of the antibiotic moenomycin A with the enzyme penicillin-binding protein 1b

Moenomycin family antibiotics: chemical synthesis, biosynthesis, and biological activity

“…4). In one approach to such analogs, treatment of 1 with different aryl diazonium salts produced, via a Japp-Klingemann reaction, compounds that contain o-nitrobenzenediazonium ( 33 ) or various substituted triazole moieties (for example, 34-38 ) 82-84 . 34 , featuring a free thiol group, provided access to biotinylated and dansylated analogs 39-41 83, 85, 86.…”

Structural and spectroscopic analysis of hydrogensquarates of glycine‐containing tripeptides

“…10 It was shown that the static electronic first-and second-hyperpolarizability of the hydrogensquarate anion are large enough to make them attractive for frequency doubling, holographic storage, or optical switching. 10 The bioactivity of squaric acid and some derivatives as inhibitors and VLA-4 integring antagonists 11 or potassium channel openers [12][13][14] have been also reported. These results have been the basis of our previous spectroscopic and structural studies of some optically active hydrogensquarate derivatives of amino acids amides 8,9 as well as of Au(III)-complexes and salts with aliphatic and aromatic di-and tripeptides.…”

Crystal structure, IR-LD spectroscopic, theoretical and vibrational analysis of valinamide ester amide of squaric acid diethyl ester

“…119.1(8) A (3,4,8) 109.1(7) A (4,8,9) 124.0(0) A (8,19,10) 135.9(7) A (9,10,13) 135.3(6) A (9,10,11) 90.0(2) A (10,11,12) 88.9(6) A (11,12,9) 94.4(6) A (10,11,14) 135.4(8) A (11,12,15) 137.7(8) A (12,15,16) 119.0(7) A (15,16,17) 110.6(7) D (1,3,4,5) 46.9 D (3,4,5,6) 112.1 D (1,3,4,8) 177.2 D (3,4,8,9) 135.2 D (4,8,9,10) 8.6 D <...>…”

“…Furthermore, squaric acid and its optically active amino acid amides crystallize noncentrosymmetrically and are of great interest for non-linear optical and electro-optical applications. In recent years, the bioactivities of squaric acid and some of its derivatives as inhibitors and VLA-4 integrating antagonists [13] or potassium channel openers [14][15][16] have been also reported. For the above reasons, the purpose of this work is to investigate the structure and IR-spectroscopic properties of the title compound, valinamide ester amide of squaric acid diethyl ester (Scheme 1) using the methods of single crystal X-ray diffraction and polarized infrared linear-dichroic (IR-LD) spectroscopy, with the latter method being based of an orientation technique of solid guest molecules as a suspension in a nematic liquid crystal.…”