Nero d’Avola and Perricone cultivars: determination of polyphenols,flavonoids and anthocyanins in grapes and wines

In 2011 vintage, the evolution of monomer and total anthocyanins, as well as of total flavonoids and polyphenols of grapes and wine of Nero d’Avola and Perricone, varieties cultivated in Sicily, was studied. Anthocyanin profiles are commonly used for grapevine cultivar identification because it is currently accepted that this trait is closely related to their genetic characteristics. The concentration of Nero d’Avola and Perricone anthocyanins was determined by HPLC-DAD.     

Microwave-Assisted Protocols Applied to the Synthesis of 1′,2,3,3′,4,4′-Hexa-O-benzylsucrose

The sucrose derivative 1′,2,3,3′,4,4′-hexa-O-benzylsucrose is a key intermediate for the chemoselective synthesis of various useful materials, such as macrocycles, crown ether analogs, and polymers. Several strategies for the synthesis of this compound were explored by applying microwave-assisted protocols, thus permitting significant reductions of time and energy compared to other routes. The outcomes of the different approaches were compared and the optimal one, in terms of yield and reproducibility, was found to be the initial protection at the positions 6 and 6′, with tert-butyldiphenylsilylchloride (TBDPSCl) in the presence of 4-(dimethylamino)pyridine (4-DMAP) and pyridine as a solvent, then perbenzylation of the remaining hydroxyl groups, followed by selective deprotection of the TBDPS groups to obtain the title compound.     

Structural Investigation of the High Spin→Low Spin Relaxation Dynamics of the Porous Coordination Network [Fe(pz)Pt(CN)4]⋅2.6 H2O

The Hoffman‐type coordination compound [Fe(pz)Pt(CN)₄] ? 2.6 H₂O (pz=pyrazine) shows a cooperative thermal spin transition at around 270 K. Synchrotron powder X‐Ray diffraction studies reveal that a quantitative photoinduced conversion from the low‐spin (LS) state into the high‐spin (HS) state, based on the light‐induced excited spin‐state trapping effect, can be achieved at 10 K in a microcrystalline powder. Time‐resolved measurements evidence that the HS→LS relaxation proceeds by a two‐step mechanism: a random HS→LS conversion at the beginning of the relaxation is followed by a nucleation and growth process, which proceeds until a quantitative HS→LS transformation has been reached.     

Use of Complexation TLC to Investigate Selected Monosulfides. Part I. Silica Impregnated with Cu(II), Co(II), Ni(II), Mn(II), Al(III), Cr(III), and Fe(III) Cations as Stationary Phase

JPC – Journal of Planar Chromatography – Modern TLC - This paper focuses on the use of complexation liquid chromatography (in its TLC mode) to investigate eleven monosulfides. In the...     

A multi-local optimization algorithm

The development of efficient algorithms that provide all the local minima of a function is crucial to solve certain subproblems in many optimization methods. A “multi-local” optimization procedure using inexact line searches is presented, and numerical experiments are also reported. An application of the method to a semi-infinite programming procedure is included. This work was partially supported by Ministerio de Educación y Ciencia, Spain, DGICYT grant PB93-0703. Author (*) was supported by the Consellería d'Educació i Ciència of the Generalitat Valenciana.     

N-Alkyl derivatives of trans-6,7-dihydroxy-1,2,3,4,4a,5,10,10b-octahyrobenzo[g]quinoline A congener of apomorphine lacking the non-oxygenated aromatic ring

A synthetic sequence leading to the title compounds began with methyl 5,6-dimethoxy-2-tetralone-3-carboxylate and involved a multi-step construction of the heterocyclic ring. The trans-fused isomer was isolated from the cyclization step. However, the possibility of formation of some cis-fused isomer cannot be precluded.     

Investigation of the association of the 1-dodecene-lauryl alcohol bicomponent system

The 1-dodecene-lauryl alcohol bicomponent system was investigated as an exemplary one, able to form the hydrogen-bonded mixed multimers, involving the olefinic double bond π-electrons. We applied the following analytical techniques: IR spectroscopy, dielectric permeativity measurements, and examinations taking advantage of the cellulose sorbents.