Search results for "TAU"

Tautomeric preferences of phthalones and related compounds

2007

Abstract Multinuclear magnetic resonance and IR spectra prove that although 2-(diacylmethyl)pyridines and 2-(diacylmethyl)quinolines are β-diketones, their proton transfer product present in chloroform solution is not ketoenol but enaminone (earlier opinions were contradictory). Quinoline derivatives are less zwitterionic by character than the respective pyridyl congeners. The β-diketone form itself may also be rarely present in the solution. X-ray data show that 2-(2(1H)-pyridinylidene)-1H-indene-1,3(2H)-dione, i.e., enaminone tautomer of 2-(pyridin-2-yl)-2H-indene-1,3-dione, is also the only form present in crystal. Ab initio calculations show that the enaminone is usually more stable tha…

(1Z,3Z)-3-[Quinolin-2(1H)-ylidene]-1-(quinolin-2-yl)prop-1-en-2-ol: An unexpected most stable tautomer of 1,3-bis(quinolin-2-yl)acetone

2009

Abstract 1 H, 13 C and 15 N NMR spectra reveal that CDCl 3 solution of 1,3-bis(quinolin-2-yl)acetone contains only ( 1Z , 3Z )-3-[quinolin-2(1 H )-ylidene]-1-(quinolin-2-yl)prop-1-en-2-ol. The proton transfer takes place between two basic centers of the molecule, which means that the process is an identity reaction by character. The situation is completely different from that detected in chloroform solution of 1,3-bis(pyridin-2-yl)acetone where three different tautomers are in equilibrium with each other. Although the proton transfers in both ( 1Z , 3Z )-3-[quinolin-2(1 H )-ylidene]-1-(quinolin-2-yl)prop-1-en-2-ol and ( 1Z , 3Z )-3-hydroxy-1-[quinolin-2(1 H )-ylidene-4-quinolin-2-yl]but-3-e…

Reply to Dr Michaudet al.

2015

There is no abstract

Volatile constituents of aerial parts ofCentaurea sibthorpii(Sect. Carduiformes, Asteraceae) from Greece and their biological activity

2008

The volatile constituents of the aerial parts of Centaurea sibthorpii [Sect. Carduiformes, Asteraceae] collected in Greece were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 63 components were identified. Fatty acids and sesquiterpenoidic compounds were the most abundant components in the oil. A study on the biological activity of the oil showed no action against Gram-positive and Gram-negative bacteria.

Volatile components from flower-heads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostál growing wi…

2008

The volatile constituents of the flowerheads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostal were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 113 components were identified. Fatty acids and hydrocarbons were the most abundant components in the oils. Caryophyllene and caryophyllene oxide were the main compounds of the sesquiterpene fraction. The study on the biological activity of the oils shows no significant activity.

Volatile components of Centaurea eryngiodes Lam. and Centaurea iberica Trev.var. hermonis Bois. Lam.,two Asteraceae growing wild in Lebanon.

2005

The volatile components of the flowerheads of Centaurea eryngioides Lam. and Centaurea iberica Trev. var. hermonis Boiss. Lam. were obtained by hydrodistillation and identified by GC and GC–MS. Altogether 91 components, mostly fatty acids and hydrocarbons, were identified.

La strada come collettore percettivo: i casi di Aprilia e Conquista del Guadiana

2020

The study of rural burgs founded during the totalitarian regimes in Spain and Italy, proposes a comparative study of urban realities characterised by peculiar elements, which show a design volition to decline the project on the territory on which it was intended to be realised, starting from an abstraction of the project up to the modifications dictated by social and logistical needs. In this paper, the case of the Spanish city Conquista del Guadiana from 1964, and the Italian Aprilia from 1936, will be deepened. Both of them are characterised by the tangential relationship with the main road axis of reference and connection with the neighbouring cities. This study aims to show that beyond …

Introduzione

2012

Il contributo è l'introduzione al libro Città, Intonaci, Colore, di cui sono curatore. I temi trattati nel volume vogliono indagare le relazioni fra luogo, identità e cultura nel quadro dell'attuale processo di globalizzazione; l'introduzione demarca i limiti spaziali e temporali della ricerca. The contribution is the introduction to the book Città, Intonaci, Colore, of which I am the editor. The topics covered in the book want to investigate the relationships between place, identity and culture in the context of the current process of globalization; the introduction demarcates the spatial and temporal boundaries of this research.

Tiesību harmonizācija Baltijas jūras reģionā pēc ES paplašināšanās: 2007. gada starptautiskās zinātniskās konferences rakstu krājums

2012

Aktuālas tiesību realizācijas problēmas : Latvijas Universitātes 69. konferences rakstu krājums

2011

Pirmais Latvijas Universitātes 69. gadskārtējās konferences juridisko zinātņu rakstu krājums. Krājuma apkopoti 48 autoru raksti, un katru no tiem ir recenzējusi divi recenzenti.