(2RS)-3-(4-Hydroxyphenyl)-2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)propanoic acid monohydrate

The title compound, C₁₇H₁₅NO₄·H₂O, derived from DL-tyrosine crystallizes as an unusual hydrogen-bonded acid-monohydrate dimer. The asymmetric unit contains two organic molecules and two water molecules. Dimers link through (aryl)O-H...O=C hydrogen bonds along the [101] direction, forming a one-dimensional chain of rings, and further associated via inversion centres (forming a chain of rings aligned in the opposite direction) generating columns. Ruffled sheets arise from interlocking of isoindole rings via π-π(arene) stacking and C-H...π(arene) interactions; C-H...O interactions generate a three-dimensional network

O-H...O, C-H...O and C-H...[pi]arene intermolecular interactions in (2S)-2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)pentanoic acid and (2S)-3-methyl-2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)butanoic acid

In the first of the title compounds, (2S)-2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)pentanoic acid, C₁₃H₁₅NO₃, prepared from L-norvaline, a hydrogen-bonded network is formed in the solid state through O-H...O=C, C-H...O=C and C-H...πarene intermolecular interactions, with shortest O...O, C...O and C...centroid distances of 2.582 (13), 3.231 (11) and 3.466 (3) Å, respectively. In the L-valine derivative, (2S)-3-methyl-2-(1-oxo-1H-2,3-dihydroisoindol-2-yl)butanoic acid, C₁₃H₁₅NO₃, O-H...O=C and Carene-H...O=C intermolecular interactions generate a cyclic R²₂(9) motif through cooperativity, with shortest O...O and C...O distances of 2.634 (3) and 3.529 (5) Å, respectively. Methylene C-H...O=Cindole interactions complete the hydrogen bonding, with C...O distances ranging from 3.283 (4) to 3.477 (4) Å

Structural systematics and conformational analyses of a 3×3 isomer grid and three chlorinated relatives

The focus of our research is to bridge solid state structural studies with computational (ab initio) modelling methods by exploring the influence of different functional groups and their position in semi-rigid small drug-like molecules.1-3 A 3×3 isomer grid of nine N-(tolyl)pyridinecarboxamides (C13H12N2O) as NxxM (x = para-/meta-/ortho-) (Scheme 1A) has been synthesised and characterised to evaluate and correlate structural relationships from both solid-state (Table 1, Figs. 1,2,4) and ab initio calculations (Fig. 3). The effect of pyridinoyl group (Nx) and methyl group (xM) substitution patterns on molecular structure and conformations (syn/anti, Scheme 1B) from calculations (gas phase and solvated forms), as well as on crystal packing and conformations in solid state is explored, allowing evaluation and rationalisation of disorder and unexpected conformations in the solid state structures

(2S)-4-Methyl-2-(1-oxo-1H-2,3-dihydroisoindol- 2-yl)pentanoic acid.

The title compound, C14H17NO3, exhibits carboxylic acid group disorder about the C—CO2 axis, with site occupancies of 0.79 (5):0.21 (5). Molecules are linked by intermolecular O—H O Ciso, C—H O Ciso and C—H (arene) interactions (iso = isoindolinone)

The Commission, the Community Method, and the Smaller Member States

This Article discusses several developments concerning the position of the Commission in the institutional structures of the European Union ( EU ) that have occurred since then. It does not touch on the many other matters that influenced the debate on the draft Constitutional Treaty, leading to its failure at referendum in France and the Netherlands; these matters include the scope of the draft Treaty, questions concerning its economic, social, and political benefits or disadvantages, the working of the Stability Pact in the Eurozone and the ongoing debate on freedom of services legislation, the purposes for which the EU was originally created and their modification, further enlargement of the EU, and so on. These subjects require separate treatment

Entry point into new trimeric and tetrameric imide-based macrocyclic esters derived from isophthaloyl dichloride and methyl 6-aminonicotinate

The one-step reaction of isophthaloyl dichloride with the 2-aminopyridine derivative (methyl 6-aminonicotinate) yields (i) a trimer-based macrocycle (EsIO)3 and (ii) a tetramer-based macrocycle (EsIO)4 in modest isolated synthetic yields (total of 25%), together with (iii) longer open-chain oligomers. The macrocyclisation relies on the semi-flexible imide hinge formed by reaction of the 2-amino(pyridine) functional group with two acyl chloride functional groups. The determining factors in macrocycle synthesis are (a) imide formation using the heteroaromatic ortho-N functionality; (b) the inherent ability of the imide to twist by 85-115 degrees from planarity (as measured by the CO...CO imide torsion angles and from computational calculations), thereby providing a hinge for macrocyclic ring closure or potentially (non)helical assembly in oligomer/polymer formation and (c) the conformational flexibility of the isophthaloyl group with meta-related carbonyl groups to twist and adopt either syn- or anti-conformations, although the syn-conformation is observed structurally for all isophthaloyl groups in both (EsIO)3 and (EsIO)4 macrocycles

Structural systematic studies and conformational analyses of a 3x3 isomer grid of fluoro-N-(pyridyl)benzamides; physicochemical correlations, polymorphism and isomorphous relationships

The effect of fluorine and pyridine N atom substitution patterns on molecular structure and conformation is probed in a 3 3 isomer grid (Scheme 1) of fluoro-N-(pyridyl)benzamides (Fxx) (C12H9N2OF, x = para-/meta-/ortho-) to evaluate and correlate structural relationships between the solid-state and ab initio calculations. Physicochemical comparisons are analysed with an extended series of three related 3 x 3 isomer grids. Our analysis integrates crystal structure analyses, computational chemistry and conformational analyses together with NMR data and physicochemical trends such as melting point analysis. This study concludes structural systematics survey of four fluoro/methyl substituted benzamide/pyridinecarboxamide isomer grids