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Novel plant growth regulators (PGRs) based on the derivatives of dehydroamino acids 2,3-dehydroaspartic acid dimethyl ester (PGR1), Z-isomer of the potassium salt of 2-amino-3-methoxycarbonylacrylic acid (PGR2) and 1-methyl-3-methylamino-maleimide (PGR3) have been synthesized and their growth-regulating properties investigated. Laboratory testing revealed their plant growth-regulating activity. PGR1 showing the most stimulating activity on all laboratory tested cultures were used in field experiments. Results showed that PGR1 is a highly effective environmentally friendly plant growth regulator with effects on different crops. Biopolymeric microcapsule formulations (chitosan/alginate microcapsule loaded with PGR) suitable for application in agriculture were prepared and characterized. Physicochemical properties and release profiles of PGRs from microcapsule formulations depend on the molecular interactions between microcapsule constituents including mainly electrostatic interactions and hydrogen bonds. The differences in the microcapsule formulations structure did not affect the mechanism of PGRs release which was identified as diffusion through microcapsules. The obtained results opened a perspective for the future use of microcapsule formulations as new promising agroformulations with a sustained and target release for plant growth regulation.

Biopolyimides poly(ATA-CBDA), made from of 4,4&prime, diamino-&alpha, truxillic acid dimethyl ester (ATA) and 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), is synthesized and measured its electric volume resistivity at various experimental conditions. The effects of film size, thickness, drying time, and the electric field strength on electric resistivity are investigated and compared with polyimide (Kapton). The electric resistivity for all polyimide and biopolyimide are distributed in the range of 1015&ndash, 1016 &Omega, cm, which shows that biopolyimide has high electrical insulation as well as polyimide. The electric resistivity strongly depends on film thickness, which suggests that electric resistivity is a function of electric field strength. The critical electric field for polyimide and biopolyimide films are determined to be 5.8 &times, 107 V/m and 3.2 &times, 107 V/m, respectively. Humidity was found to strongly affect the electric resistivity, ~1016 &Omega, cm at 34% RH and ~1013 &Omega, cm at 60% RH for both polyimide and biopolyimide films.

We report the design, synthesis, and electron spin relaxation properties of hydrophilic tetracarboxylate ester pyrroline nitroxides 1 and 2, which serve as models in the search for new spin labels for DEER distance measurement at room temperature. The nitroxides are designed to have the methyl groups further away from the N–O spin site to decrease the inequivalent couplings of the unpaired electron to the methyl protons that shorten Tm at T > 70 K in currently used labels. The key step in the synthesis of 1 and 2 is the reaction of the dianion of pyrrole-1,2,5-tricarboxylic acid tert-butyl ester dimethyl ester with electrophiles such as methyl chloroformate and methyl bromoacetate. Structures of 1 and 2 are confirmed by X-ray crystallography. Studies of electron spin relaxation rates in rigid trehalose/sucrose matrices reveal approximately temperature independent values of 1/Tm for 1 and 2 up to about 160 K and modest temperature dependence up to 295 K, demonstrating that increasing the distance between the nitroxide moiety and methyl groups is effective in lengthening Tm at T > 70 K.

This paper reports on the first phytochemical analysis ever performed on Jasminum tortuosum Willd. This analysis, mainly carried out by means of column chromatography separation, NMR spectroscopy and mass spectrometry, led to the isolation and the identification of four compounds, namely the lignans ginkgool (1) and olivil-4′-O-β-glucopyranoside (2) and the secoiridoids oleoside dimethyl ester (3) and oleoside 11-methyl ester (4). The presence of these compounds is significant from a chemotaxonomic point of view, confirming the correct botanical classification of the species and, from a phytochemical standpoint, may suggest its possible use in the ethno-medicinal field.

This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing aids (CEF Panel) deals with the safety assessment of 1,2,3,4‐tetrahydronaphthalene‐2,6‐dicarboxylic acid, dimethyl ester (TDCM) for use as a co‐monomer to manufacture polyester layers. The polyester layer is not intended to be in direct contact with food. The finished multilayer articles are intended for packaging aqueous, acidic and low alcoholic foodstuffs. Contact conditions include sterilisation followed by long‐term storage at room temperature. No thermal degradation of TDCM is expected during the manufacture of the middle polyester layer and of the multilayer articles. Total mass transfer of the substance from a polyester monolayer was calculated to be up to 0.032 mg/kg food. Based on three in vitro genotoxicity tests, the CEF Panel considered that the substance does not raise concern for genotoxicity. When tested behind a polypropylene layer, migrating TDCM‐related oligomers, their oxidation products and other related reaction products were identified. The major components were TDCM dimers. When tested behind a cyclo‐olefin polymer layer, none of the TDCM‐related substances were found to migrate. Based on the lack of genotoxicity of the co‐monomer, the ester nature of the oligomers and on (quantitative) structure–activity relationship ((Q)SAR) analysis, the CEF Panel considered that there is no indication of genotoxicity for the oligomers, their oxidation products and other TDCM‐related reaction products. The CEF Panel concluded that the substance is not of safety concern for the consumer if used as a co‐monomer for the manufacture of a polyester layer intended to be used as an inner (non‐food contact) layer of a multilayer material for contact with foods simulated by simulants A, B, C, D1 (as set in Regulation (EU) 10/2011). The migration of the sum of the substance and the dimers (cyclic and open chain) should not exceed 0.05 mg/kg food.

Depending on their relative orientation, coupled oscillating carbonyl groups provide a VCD spectrum with a characteristic CO bond stretching region showing a strong bisignate VCD feature, which can be readily predicted adopting long available semiempirical methods. The extended coupled oscillator (ECO) formalism has been used to assign the absolute configuration of a recently synthesized chiral 3-substituted isoindolinone. The prediction of ( S ) configuration for the (−) enantiomer has been confirmed by quantum mechanical calculations.

Novel semisynthetic analogs of salvinorin A, a full agonist having extraordinary affinity as well as selectivity for the κ-opioid receptor (KOR), were obtained in good yields. The derivatives are remarkable for their unusual and unique hemiacetal structure in the salvinorin series of compounds. The formation of the hemiacetal occurs with epimerization at C-12, thus preserving the original configuration of salvinorin A. The dimethyl ester derivative of the hemiacetal was found to have an affinity for both KOR and MOR (μ-opioid receptor).

An efficient, stereoselective synthetic strategy to d - threo -3-hydroxyaspartic acid was developed. Starting from l -(2 S ,3 S )- N -benzoyl-3-hydroxyaspartic acid dimethyl ester by a Deoxo-fluor-catalyzed cyclization reaction, an inversion of configuration at the β-center ( erythro isomer), was observed. A base-induced epimerization reaction led to the d - trans -isomer, which was hydrolyzed to give d - threo -3-hydroxyaspartic acid with excellent stereoselectivity and overall yield. Starting from d - threo -3-hydroxyaspartic acid, l - threo -oxazolines can be stereoselectively synthesized.

Simple and efficient synthesis of several new 1,3,7-trisubstituted bicyclo[3.3.1]nonane derivatives [e.g. 1-hydroxybicyclo[3.3.1]nonane-3,7-dicarboxylic acid (4), dimethyl ester 1-hydroxybicyclo[3.3.1]nonane-3,7-dicarboxylic acid (5), di-methyl ester-1-methoxybicyclo[3.3.1]nonane-3,7-dicarboxylic acid (5a), 1-hydroxy-3,7-di(hydroxymethyl)bicyclo[3.3.1]nonane (6), 1-hydroxy-3,7-di(bromomethyl)bicyclo[3.3.1]nonane (7), 1-bromo-3,7-di(bromomethyl)bicyclo[3.3.1]nonane (8) and 1-bromo-3,7-di(cyanomethyl)bicyclo[3.3.1]nonane (9)] is described.

Single crystals of the title compound, C10H11NO4, an intermediate in the industrial synthesis of yellow azo pigments, were obtained from the industrial production. The molecules crystallize as centrosymmetic dimers connected by two symmetry-related N—H...O=C hydrogen bonds. Each molecule also contains an intramolecular N—H...O=C hydrogen bond. The dimers form stacks along the a-axis direction. Neighbouring stacks are arranged into a herringbone structure.

A series of calix (aza-)crowns 6a-f and 11a,b has been prepared by reaction of either calix dimethyl ester 4 or calix diacid dichloride 10 with an appropriate diamine. The complexation with both di- and trivalent cations has been qualitatively studied using fast-atom bombardment mass spectrometry.

The acid-catalyzed isomerization of the diglyceride analog (1,2,3/0)-1,2-dipalmitoylcyclopentane-1,2,3-triol has been used to generate syn-syn-1,3-diacyl-cyclopentane-1,2,3-triol, a required intermediate in the synthesis of a symmetrical all-cis-1,2,3/0-2P cyclopentanoid phosphatidic acid analog. The all-cis cyclo-phosphatidic acid analog has therefore been obtained in the free acid form and as the diphenyl ester, dimethyl ester, and dipotassium salt derivatives. The compounds have been characterized by microanalysis and spectroscopic methods. The 1,2,3/0-2P analog is now available for comparative studies with the corresponding all-trans cyclophosphatidic acid (1,3/2-2P).

We have made a survey of the published literature on the mutagenicity, in procaryotes, of insecticides, acaricides, and nematocides. The importance of the study of the possible genotoxic effects of pesticides is evident: atthe great majority of people all over the world are exposed daily to minute amounts of pesticides present in their food, and a smaller number of people (agricultural workers and workers in pesticide plants) are exposed to even higher doses of these substances.

Disodium, calcium and (+)-α-phenethylammonium salts of (-)-trans-1,2-epoxypropylphosphonic acid, the sodium salt of the monomethyl ester, and the dimethyl ester of this acid have been studied by 1H, and 13C NMR, IR and Raman spectroscopy. From the NMR study it can be deduced that the steric factors are mainly responsible for the molecular arrangement of these compounds in solution. IR and Raman data suggest the existence of rotational isomerism in the dimethyl ester derivative. © 1986.

Background Twenty-seven extracts from 26 plants were identified as photo-cytotoxic in the course of our bioassay guided screening program for photosensitisers from 128 extracts prepared from 64 terrestrial plants in two different collection sites in Malaysia - Royal Belum Forest Reserve in the State of Perak and Gunung Nuang in the State of Selangor. One of the photo-cytotoxic extracts from the leaves of Phaeanthus ophtalmicus was further investigated. Results The ethanolic extract of the leaves from Phaeanthus ophtalmicus was able to reduce the in vitro viability of leukaemic HL60 cells to < 50% when exposed to 9.6 J/cm2 of a broad spectrum light at a concentration of 20 μg/mL. Dereplication of the photo-cytotoxic fractions from P. ophthalmicus extracts based on TLC Rf values and HPLC co-injection of reference tetrapyrrolic compounds enabled quick identification of known photosensitisers, pheophorbide-a, pheophorbide-a methyl ester, 132-hydroxypheophorbide-a methyl ester, pheophytin-a and 151-hydroxypurpurin 7-lactone dimethyl ester. In addition, compound 1 which was not previously isolated as a natural product was also identified as 7-formyl-151-hydroxypurpurin-7-lactone methyl ester using standard spectroscopic techniques. Conclusions Our results suggest that the main photosensitisers in plants are based on the cyclic tetrapyrrole structure and photosensitisers with other structures, if present, are present in very minor amounts or are not as active as those with the cyclic tetrapyrrole structure.