Chiral terpene auxiliaries V: Synthesis of new chiral γ-hydroxyphosphine oxides derived from α-pinene.

New chiral regioisomeric γ-hydroxyphosphine ligands were synthesized from α-pinene. The key transformation was the thermal [2,3]-sigmatropic rearrangement of allyldiphenylphosphinites, obtained from (1R,2R,4S,5R)-3-methyleneneoisoverbanol and (1R,2R,3R,5R)-4-methyleneneoisopinocampheol, to allylphosphine oxides. Hydroxy groups were introduced stereoselectively through a hydroboration-oxidation reaction proceeding from the less hindered site providing a trans relationship between the hydroxy and the phosphine substituents.

New Water-Soluble (Iminomethyl)benzenesulfonates Derived from Biogenic Amines for Potential Biological Applications.

In this paper, a highly efficient and straightforward method for synthesizing novel Schiff bases was developed by reacting selected biogenic amines with sodium 2-formylbenzene sulfonate and sodium 3-formylbenzene sulfonate. 1H and 13C NMR, IR spectroscopy, and high-resolution mass spectrometry were used to characterize the new compounds. The main advantages of the proposed procedure include simple reagents and reactions carried out in water or methanol and at room temperature, which reduces time and energy. Moreover, it was shown that the obtained water-soluble Schiff bases are stable in aqueous solution for at least seven days. Additionally, the antioxidant and antimicrobial activity of synthesized Schiff bases were tested.

Determination of Biogenic Amine Level Variations upon Storage, in Chicken Breast Coated with Edible Protective Film.

A new chitosan-based protective film containing rosemarinic acid (0.282% w/w) has been elaborated. The film was formed from a water-oil emulsion system and applied to poultry meat samples using a dip-coating technique. Various physicochemical parameters of the coatings, such as thickness, Young's modulus, elongation at break, water vapor transmission rates, and antioxidant activity, were tested with free-standing film samples peeled from a Petri dish. Compared to neat chitosan films obtained similarly, new films cast from the emulsion showed significantly better elasticity (Young's modulus was diminished from 1458 MPa to about 29 MPa). Additionally, barrier properties for moisture transition decreased from 7.3 to 5.8 g mm m-2 day-1 kPa-1. The coated poultry samples were subsequently evaluated in juxtaposition with uncoated ones in a storage test. Levels of selected biogenic amines (histamine, tyramine, tryptamine, phenylethylamine, putrescine, cadaverine, spermine, and spermidine), total bacterial count, and lipid oxidation levels in the meat samples were analyzed during storage at 4 °C (up to 96 h). The results obtained for the biogenic amines, total bacterial content, calculated biogenic amine index, and the ratio of spermidine to spermine in meat samples suggest the advantage of the proposed coatings with rosmarinic acid in protecting poultry meat against environmental factors and rapid spoilage.

The Selection of the Best Derivatization Reagents for the Determination of Polyamines in Home-Made Wine Samples.

The procedures of putrescine, spermine, spermidine, and cadaverine derivatization using 2-chloro-1,3-dinitro-5-(trifluoromethyl)benzene, 1-fluoro-2-nitro-4-(trifluoromethyl) benzene, and 3,5-bis-(trifluoromethyl)phenyl isothiocyanate for chromatographic determination in home-made wine samples are compared in the present study. The procedures discussed were compared regarding simplicity, linearity, precision, and accuracy. The polyamines derivatives were isolated and characterized by X-ray crystallography and 1H, 13C, and 19F NMR spectroscopy. The obtained structures of aliphatic amines showed that all amino groups, four in spermine, two in putrescine and cadaverine, and three in spermidine, regardless of the applied reagent, were substituted. The applicability of the described procedures was tested during the chromatographic analysis of the compounds' content in home-made wines. For this purpose, a simple and environmentally friendly sample preparation procedure was developed. The obtained results present the derivatization of polyamines with 1-fluoro-2-nitro-4-(trifluoromethyl)benzene as a better choice for the determination of these compounds in food samples.

Simple and Effective Derivatization of Amino Acids with 1-Fluoro-2-nitro-4-(trifluoromethyl)benzene in a Microwave Reactor for Determination of Free Amino Acids in Kombucha Beverages.

Kombucha is a fermentation product of sweetened tea with a symbiotic culture of acetic acid and yeast bacteria, consumed worldwide for its health-promoting properties. Few reports can be found about free amino acids among the health-promoting compounds found and determined in kombucha. These compounds influence the sensory properties of kombucha, and they are precursors of bioactive compounds, which have a significant role as neurotransmitters and are involved in biological functions. The presented studies proposed a convenient, simple, and "more green" procedure of the synthesis of amino acid derivatives, assisted by microwave energy, followed by chromatographic determination. The structure of 1-Fluoro-2-nitro-4-(trifluoromethyl)benzene was used as a suitable reagent for the derivatization of free amino acids in fermented kombucha beverages prepared from selected dry fruit such as Crataegus L., Morus alba L., Sorbus aucuparia L., Berberis vulgaris L., Rosa canina L., and black tea. The obtained results were discussed regarding the tested beverages' application as a source of amino acids in one's daily diet. The obtained results point out that the proposed microwave-assisted derivatization procedure prior to HPLC analyses allows for a significant time reduction and the limitation of using organic reagents.