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Elderberry (Sambucus nigra L.) is a widespread deciduous shrub, of which the fruits (elderberries) are used in the food industry to produce different types of dietary supplement products. These berries have been found to show multiple bioactivities, including antidiabetic, anti-infective, antineoplastic, anti-obesity, and antioxidant activities. An elderberry extract product, Sambucol®, has also been used clinically for the treatment of viral respiratory infections. As the major components, phenolic compounds, such as simple phenolic acids, anthocyanins and other flavonoids, and tannins, show promising pharmacological effects that could account for the bioactivities observed for elderberries. Based on these components, salicylic acid and its acetate derivative, aspirin, have long been used for the treatment of different disorders. Dapagliflozin, an FDA-approved antidiabetic drug, has been developed based on the conclusions obtained from a structure–activity relationship study for a simple hydrolyzable tannin, β-pentagalloylglucoside (β-PGG). Thus, the present review focuses on the development of therapeutic agents from elderberries and their small-molecule secondary metabolites. It is hoped that this contribution will support future investigations on elderberries. [ABSTRACT FROM AUTHOR]

The synthesis of a series of monovalent metal ions with a new trispyrazolyl ligand bearing hemilabile ether appendages is reported.

Three cyclopentadienyllithium compounds with the tethered, T, ligand - N(CH3CH2OCH3)2 are described. Results reveal that the ligand tether and the stereochemistry around Li(super +) accommodate to maintain the structural integrity of Cp(super -)Li(super +).

A series of beta-diiminato complexes of the form (BDI-3)MX where (BDI-3)=[CH(CMeNC6H4-2-OMe)2]; M=Zn, Mg; X=O(super i)Pr, O(super t)Bu, or N(SiMe3)2 is synthesized. The (BDI-3) ligand is bidentate in (BDI-3)ZnN(SiMe3)2 and tetradentate in (BDI-3)MgN(SiMe3)2.

The observations involving the fate of conformationally equilibrium brating 1,3,5,7-octatetraenyl bisenolates with regard to their preferred mode of conrotatory cyclization and other chemical transformations are described. The existence of this class elusive doubly charged helical intermediates came to light during several prior investigations.

A study is carried out on the binding of propylene oxide to LM(super +), where L= tetraphenylporphyrin and salen and M = AL(III), Cr(III), and Co(III) in the gas phase in an electrospray tandem mass spectrometer. The results show remarkable differences in coordination chemistry among these metals and details of the solid-state studies and activities in the polymerization reactions are discussed.

A series of monomeric amide or aryloxide complexes of the form LCaX, where L = CH[CMeNC6H3-2,6-Pr2]2, CH[CMeNC6H4-2-OMe]2, a bulky tris-pyrazolyl borate, Tp(super iPr) or Tp(super tBu) or 9-BBN-pz2 and X = N(SiMe3)2 or OC6H3-2,6-Pr2 was prepared and characterized and investigated in the ring-opening polymerizations of lactide.

The synthesis of a series of compounds are made where M-Mo or W, L = a thienyl, or terthienyl carboxylate, and L are corresponding thienyl dicarboxylate. The electronic absorption spectra are reported and show intense metal-to-ligand charge transfer bands.

Research has been conducted on the alkali metal ions Li (super)+, Na (super)+ and K (super)+ in the constrained inositol orthoformate derivatives. The structural features conductive to the complexation of these metal ions have been investigated in solution, in the solid state and in the gas phase via the electrospray ionization mass spectroscopy and the details are discussed.

Research has been conducted on the zinc Schiff-base ligand complexes of the form LZnX where X is an aryloxide or amide and L is a ligand. The preparation and characterization of these complexes have been carried out and the results are discussed.

Research into the development of a ring-closing metathesis strategy for incorporating sulfone groups into polybicyclic molecules is presented.

ReH5(Cyttp) (Cyttp=PhP(CH2CH2CH2PCy2)2) was found to adopt a triangulated dodecahedral structure in the solid, with four hydrides in the A sites and the remaining donor atoms in the B sites. It undergoes protonation by HSbF6 to the nonclassical polyhydride (ReH4(eta2-H2)(Cyttp))SbF6, insertion reactions with X=C=S (X=S,p-O2NC6H4N, EtOC(O)N) to produce ReH4(SCH=X)(Cyttp), and reactions with (C7H7)BF4 in the presence of L (L=MeCN, t-BuNC, CyNC, P(OMe)3) to produce (ReH4L(Cyttp))BF4.

Synthesis of Fischer-type rhenacyclobutadiene complexes (CO)4ReC(R)C(CO2Me)C(OEt) proceeds through the interaction of Na(Re(CO)5) with induced acetylenes to yield intermediate rhenacyclobutenone complexes. These complexes are subjected to alkylation with Et3OPF6 to afford the final product. Fisher-type rhenacyclobutadiene complexes have a characteristically reduced oxidation state transition metal. These structures contain an oxygen heteroatom coupled to one alpha-carbon atom of the ring which effects its stability. Their reactions with phosphines and (NH4)2(Ce(No3)6) are also studied.

The cis-(n.3.1)bicyclic ketones that featured seven or less polymethylene (n) belts diaxially extended the n chain, while those that had n belts as high as nine, permitted a diequatorial geometry conformation. The application of X-ray crystallographic analysis made it possible to determine the conformational switchover that happened as the n belts increased from seven to nine. In addition, substitution reactions were performed to observe the effect of stereochemical crossover on the facial stereoselectivity of the bicyclic ketone and its derivatives.

Variable-temperature NMR studies are conducted to demonstrate that the conformational restraints imposed by selected backbones increase the activation barrier for the helical isomerization in (Z,Z)-dienes that are generated in the cyclization of the diynes. The reaction chemistry could be applied to synthesize highly functionalized dibenzocyclooctadienes which adorn the carbon frames of several important cytotoxic natural products.

The established Weiss-Cook condensation takes an unexpected turn when dimethyl 1,3-acetonedicarboxylate reacts with cis-6-cyclodecene-1,2-dione. Instead of the (n.3.3)propellane, the bisadduct turns out to be an unsymmetric monoketo tetracarboxylate with a unique diquinane form where three stereogenic centers with carbomethoxy groups are fixed in an all-cis plane. Analysis of the conformational energies of analogous systems shows that the unusual adduct is a result of kinetic bias by the cyclodecene ring seeking to find a more energetically tenable conformation. Its less strained dodecane cousin faithfully obeys the Weiss-Cook rule and yields the expected propellane.

Efficient synthetic routes are described for the four isomers of the title ketone. The entry has started from the Wieland-Miescher homologue whose pair of carbonyl groups are amenable to regiochemical manipulation and the regiochemical trends are correlated with B3LYP/6-31G* calculations.

The addition of elemental bromide dissolved in C[H.sub.2][Cl.sub.2] to para-disubstituted benzodiaocines, where X is the same (H, C[H.sub.3], Br, OMe, N[O.sub.2]) or a different substituent as X and Y (C[H.sub.3], Br; OMe, N[O.sub.2]) has proceeded with competition between two pathways. The regio- and stereoselectivities have established the capability of sulfonamide nitrogen centers to engage in neighboring group participation.

The ability of sulfonamido nitrogen to enter into neighboring group participation is established in two different reaction settings. The first is disclosed during the bromination of the benzodiazocine in dichloromethane and the second during the base treatment of [Br.sub.2] (2.0 equiv) en route to allene.

The preparation of (R,R)- and (S,S)-salen Al(OR) complexes (R = Et, C[H.sub.2][super i]Pr, C[H.sub.2][super t]Bu and C[H.sub.2]CH(S)MeCl) are described along with their reactions with rac-lactide (salen = N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediamino). The studies have shown that the relative rate of trans-esterification is slower than the rate of LA enchainment and that the rate of epimerization is the slowest reaction in the system.

The synthesis of 12 hexacyclic tetrahydrofuran isomers is described and the alkali metal ion selectivities of the 12 hexamers are analyzed by a picrate extraction method and by electrospray ionization mass spectrometry (ESI-MS). Each hexamer has displayed a preference for lithium ion complexation relative to sodium or potassium ion complexation.

A viable synthetic route is developed for a doubly unsaturated bicyclo[4.2.1]nonanyl sultam featuring the nitrogen at the bridgehead site and the sulfonamide sulfur on the single atom bridge. The direct irradiation of bicyclic dienyl sultam (9) resulted in valence isomerization to provide the endo-cyclobutene 30 and heating 9 with endo-bornyltriazolinedione in ethyl acetate solution gave rise to 33 and its diastereomer.

The synthesis, conformational properties, and photoresponsive behaviour of a series of oligomers constructed using azobenzenes as a structural component geometrically required for folding are described. It is observed that the oligomers adopt multi-turn helical conformation in the solid state that is stable in both polar and nonpolar solvents when in the E form.

Various substituted dirhodium tetraformamidinate complexes, Rh2(R-form)(sub 4) (R= p-CF3, p-Cl, p-OCH3,M-OCH3, form=N,N'-diphenylformamidinate), and the new complex Rh2(tpgu)(sub 4) (tpgu=1,2,3-triphenylguanidinate) are investigated as potential agents for the photoremediation of saturated halogenated aliphatic compounds, RX. The synthesis and characterization of the complexes is reported, and the crystal structure of Rh2(tpgu)(sub 4) is presented.