The dimethyl-, di-n-butyl-, and diphenyltin(IV) dithiocarbamate (dtc) complexes [{R2Sn(L-dtc)}x] 1-7 (1, L = L1, R = Me; 2, L = L1, R = n-Bu; 3, L = L2, R = Me, x = infinity; 4, L = L2, R = n-Bu; 5, L = L3, R = Me, x = 2; 6, L = L3, R = n-Bu, x = 2; 7, L = L3, R = Ph, x = 2) have been prepared from a series of secondary amino acid (AA) homologues as starting materials: N-benzylglycine (alpha-AA derivative = L1), N-benzyl-3-aminopropionic acid (beta-AA derivative = L2), and N-benzyl-4-aminobutyric acid (gamma-AA derivative = L3). The resulting compounds have been characterized by elemental analysis, mass spectrometry, IR and NMR ((1)H, (13)C, and (119)Sn) spectroscopy, thermogravimetric analysis, and X-ray crystallography, showing that in all complexes both functional groups of the heteroleptic ligands are coordinated to the tin atoms. By X-ray diffraction analysis, it could be shown that [{Me2Sn(L2-dtc)}x] (3) is polymeric in the solid state, while the complexes derived from L3 (5-7) have dinuclear 18-membered macrocyclic structures of the composition [{R2Sn(L3-dtc)}2]. For the remaining compounds, it could not be established with certainty whether the structures are macrocyclic or polymeric. A theoretical investigation at the B3LYP/SBKJC(d,p) level of theory indicated that the alpha-AA-dtc complexes might have trinuclear macrocyclic structures. The macrocyclic complexes 5-7 have a double-calix-shaped conformation with two cavities large enough for the inclusion of aliphatic and aromatic guest molecules. They are self-complementary for the formation of supramolecuar synthons that give rise to 1D molecular arrangements in the solid state. Preliminary recognition experiments with tetrabutylammonium acetate have shown that the [{R2Sn(L3-dtc)}2] macrocycles 6 and 7 might interact simultaneously with anions (AcO(-)), which coordinate to the tin atoms, and organic cations (TBA(+)), which accommodate within the hydrophobic cavity (ion-pair recognition).

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The potassium bis-dithiocarbamate (bis-dtc) salts of 1,3-bis(benzylaminomethyl)benzene (1,3-Bn-ambdtc), 1,3-bis(iso-butylaminomethyl)benzene (1,3-(i)Bu-ambdtc), 1,4-bis(benzylaminomethyl)benzene (1,4-Bn-ambdtc), and 1,4-bis(iso-butylaminomethyl)benzene (1,4-(i)Bu-ambdtc) were reacted with three different diorganotin dichlorides (R2SnCl2 with R = Me, (n)Bu, and Ph) in 1:1 stoichiometric ratios to give the corresponding diorganotin bis-dithiocarbamates. Additionally, the dimethyltin bis-dithiocarbamate of 1,1'-bis(benzylaminomethyl)ferrocene (1,1'-Bn-amfdtc) was prepared. The resulting complexes have been characterized as far as possible by elemental analysis, FAB(+) mass spectrometry, IR and NMR ((1)H, (13)C, and (119)Sn) spectroscopy, and single-crystal X-ray diffraction, showing that the tin complexes are dinuclear 24- and 26-membered macrocyclic species of composition [{R2Sn(bis-dtc)}2]. As shown by (119)Sn NMR spectroscopy, the tin centers are hexa-coordinated in all cases; however, two different coordination environments are possible, as detected by single-crystal X-ray diffraction. In the dimethyltin derivatives of 1,3-Bn-ambdtc, 1,3-(i)Bu-ambdtc, 1,4-Bn-ambdtc, and 1,1'-Bn-amfdtc and the di-n-butyltin derivative of 1,3-(i)Bu-ambdtc, the metal atoms are embedded in skewed-trapezoidal-bipyramidal coordination polyhedra with asymmetrically coordinating trans-oriented dtc groups. In contrast, in the diphenyltin derivative 1,3-(i)Bu-ambdtc, the metal centers have distorted octahedral coordination with symmetrically coordinating cis-oriented dtc functions. Thus, for the complexes derived from 1,3-Bn/(i)Bu-ambdtc, two different macrocyclic structures were observed. In the dimethyl- and di-n-butyltin derivatives, the bridging bis-dtc ligands adopt U-shaped conformations, while in the case of the diphenyltin derivative, the conformation is L-shaped. Furthermore, two different macrocyclic ring conformations can occur, which differ in the spatial orientation of the substituents attached to the nitrogen atoms (Bn or (i)Bu). The dimethyltin derivatives of 1,4-Bn-ambdtc and 1,1'-Bn-amfdtc have cavities, in which aromatic rings are accommodated in the solid state.

Dibutyl phthalate (DBP) is a widely used plasticizer, whose presence in the environment as a pollutant raises concern because of its endocrine-disrupting toxicity. Growth kinetics, glucose uptake, biodegradation constant of DBP (), half-life of DBP biodegradation () and percentage of removal efficiency (%) were evaluated for grown on media containing glucose and different concentrations of DBP (500 and 1000 mg/l). Intermediate compounds of biodegraded DBP were identified by GC-MS and a novel DBP biodegradation pathway was proposed on the basis of the intermolecular flow of electrons of the intermediates identified using quantum chemical modeling. degraded 99% of both 1000 and 500 mg of DBP/l after an incubation period of 168 and 228 h, respectively. % was 99.5 and 99.3 for 1000 and 500 mg of DBP/l, respectively. The was 0.0164 and 0.0231 h for 500 and 1000 mg of DBP/l, respectively. DBP was fully metabolized to fumaric and malic acids, which are compounds that enter into the Krebs cycle. has a promising ability for bioremediation of environments polluted with DBP because it efficiently degrades DBP and uses high concentrations of this compound as carbon and energy source.

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In recent decades, the food industry has focused on the search for potential sources of anthocyanins that are able to provide color to replace synthetic dyes and at the same time provide health benefits through food products. Thus, in the present work, we propose the Dahlia pinnata flower as a potential source of anthocyanins. The dahlia is a native, annual flower from Mexico with a wide diversity of shapes and colors. The ancestral use of the flower in several dishes, its abundance, and the intense color of the flowers known as black make the D. pinnata flower a suitable candidate to be considered as a potential source of anthocyanins. Thus, the aim of this research is the determination of its nutritional composition, anthocyanin profile, and antioxidant activity. For this purpose, proximate composition of petals was determined by the AOAC standard methods. Anthocyanins were extracted from the dried petals of the flower with 0.1% HCl in methanol and 70% aqueous acetone solution and purified through Amberlite-XAD7-HP resin. Then, the purified extracts were analyzed for antioxidant activity by the DPPH method and the anthocyanin profile was characterized by HPLC and UPLC-MS/MS. Results showed that D. pinnata flowers have a proximate composition similar to other important edible flowers with a high level of moisture (87%-92%) and fiber (6%-7%). The antioxidant activity of both purified extracts was considerable (2.6-12 g/ml) compared to other sources of anthocyanins. The anthocyanin profile of the purified extracts contains four main anthocyanins: delphinidin-3-glucoside, delphinidin-3-rutinoside, pelargonidin-3-sambubioside-5-glucoside, and peonidin-3-sambubioside-5-glucoside, the last two being uncommon as major anthocyanin components in other plant sources. K E Y W O R D Santhocyanin, anthocyanin profile, antioxidant activity, dahlia flower, UPLC-MS/MS Practical Application: We present a potential and novel source of anthocyanins based on anthocyanin content and antioxidant activity of Dahlia pinnata petals.