1.Gel sculpture: moldable, load-bearing and self-healing non-polymeric supramolecular gel derived from a simple organic salt.
Sahoo P1, Sankolli R, Lee HY, Raghavan SR, Dastidar P. Chemistry. 2012 Jun 25;18(26):8057-63. doi: 10.1002/chem.201200986. Epub 2012 May 24.
An easy access to a library of simple organic salts derived from tert-butoxycarbonyl (Boc)-protected L-amino acids and two secondary amines (dicyclohexyl- and dibenzyl amine) are synthesized following a supramolecular synthon rationale to generate a new series of low molecular weight gelators (LMWGs). Out of the 12 salts that we prepared, the nitrobenzene gel of dicyclohexylammonium Boc-glycinate (GLY.1) displayed remarkable load-bearing, moldable and self-healing properties. These remarkable properties displayed by GLY.1 and the inability to display such properties by its dibenzylammonium counterpart (GLY.2) were explained using microscopic and rheological data. Single crystal structures of eight salts displayed the presence of a 1D hydrogen-bonded network (HBN) that is believed to be important in gelation. Powder X-ray diffraction in combination with the single crystal X-ray structure of GLY.1 clearly established the presence of a 1D hydrogen-bonded network in the xerogel of the nitrobenzene gel of GLY.
2.Efficacy of fumagillin against Thelohanellus kitauei infection of Israel carp, Cyprinus carpio nudus.
Rhee JK1, Kim HC, Park BK. Korean J Parasitol. 1993 Mar;31(1):57-65.
The potential of fumagillin dicyclohexylamine salt to treat and prevent intestinal giant-cystic disease in Israel carp, Cyprinus carpio nudus, was monitored in field experimental studies. In experiment 1 (therapeutic), most fish were already naturally infected with more advanced stage of Thelohanellus kitauei. Fumagillin was administered to fish (mean body weight of 830 g) for a period of one month at a dose of 10.62 mg in the first group and 5.3 mg in the second group per fish per day. In experiment 2 (prophylactic), most fish also were already naturally infected with an early developmental stage of the protozoa and fish (average body weight of 484 g) were administered fumagillin for 45 days at a dose of 3.95 mg per fish per day. In both experiments, the cumulative mortalities of fish and the extrusion rates of the polar filaments of the spores were significantly decreased in a dose-independent fashion. In experiment 2 no dead fish were observed.
3.In vitro evaluation of the clastogenicity of fumagillin.
Stevanovic J1, Stanimirovic Z, Radakovic M, Stojic V. Environ Mol Mutagen. 2008 Oct;49(8):594-601. doi: 10.1002/em.20409.
Fumagillin, an antibiotic compound produced by Aspergillus fumigatus, is effective against microsporidia and various Amoeba species, but is also toxic when administered systemically to mammals. Furthermore, a recent in vivo study by Stanimirovic Z et al. 2007: (Mutat Res 628:1-10) indicated genotoxic effects of fumagillin. The aim of the present study was to investigate and explain the clastogenic effects of fumagillin (in the form of fumagillin dicyclohexylamine salt) on human peripheral blood lymphocytes in vitro by sister-chromatid exchanges (SCE), chromosome aberrations (CA), and micronucleus (MN) tests. The mitotic index (MI), proliferation index (PI), and nuclear division index (NDI) were calculated to evaluate the cytotoxic potential of fumagillin. Five concentrations of fumagillin (0.34, 0.68, 1.02, 3.07, and 9.20 microg/ml) were applied to lymphocyte cultures. All the tested concentrations of fumagillin increased the frequency of SCE per cell significantly (P < 0.
4.Structure elucidation and conformational properties of a novel bioactive clerodane diterpene using a combination of high field NMR spectroscopy, computational analysis and X-ray diffraction.
Kolocouris A1, Mavromoustakos T, Demetzos C, Terzis A, Grdadolnik SG. Bioorg Med Chem Lett. 2001 Mar 26;11(6):837-40.
The structure of a novel CC clerodane type diterpenoid, namely (+)-19-acetoxy-cis-clerodan-3-ene-15-oic acid 1 was elucidated and its conformational properties were explored using a combination of high field NMR spectroscopy and computational analysis. The structural analysis provided results consistent with those obtained by a single X-ray diffraction study of its dicyclohexylammonium salt. The new clerodane type diterpene isolated in large quantities from Cistus monspeliensis L. leaves was found to exhibit significant antibacterial activity against Staphyloccoci (MIC50 = 0.085 mM) and therefore represents a promising lead compound. Interestingly the deacetylated derivative 2 of compound 1 was inactive.
