Derivatives of methylenediphosphonic acid possess wide spectra of biological activities and are used in enzymology as research tools as well as in practical medicine. Carbonyl diphosphonic acid is a promising starting building block for synthesis of functionally substituted methylenediphosphonates. Investigation of the interaction of carbonyl diphosphonic acid with hydroxylamine clearly demonst...

In the title compound, C(21)H(18)O(5), the dihedral angle between the naphthalene ring system and the benzene ring is 86.65 (6)°. The bridging carbonyl C-C(=O)-C plane makes dihedral angles of 83.57 (7) and 20.21 (8)°, respectively, with the naphthalene ring system and the benzene ring. The ester O-C=O plane and the benzene ring are almost coplanar, making a dihedral angle of 3.81 (18)°. The tw...

The alkynyl bond of the title compound, C(14)H(19)NO, has a length of 1.170 (5) Å. The amide function shows a trans conformation with respect to the carbonyl group characterized by the torsion angle O-C-N-H of -176 (2)°. There is an inter-molecular N-H⋯O hydrogen bond between the amide function and the carbonyl group. In addition, weak inter-molecular hydrogen bonds stabilize the crystal struct...

When the hydrate reverts to starting materials, either of its two oxygen atoms must leave: one came from the water and one from the carbonyl group, so 50% of the time the oxygen atom that belonged to the carbonyl group will be lost. Usually, this is of no consequence, but it can be useful. For example, in 1968 some chemists studying the reactions that take place inside mass spectrometers needed...

The structure and absolute configuration of the title compound, C8H11NO4, which is a known quorum-sensing modulator, have been determined. The mol-ecule exhibits signs of an intra-molecular attractive carbon-yl-carbonyl n→π* inter-action between the amide and lactone ester groups, specifically - a short contact of 2.709 (2) Å between the amide oxygen atom and ester carbon atom, approach of the ...

An n = π* interaction between neighboring carbonyl groups has been postulated to stabilize protein structures. Such an interaction would affect the (13)C chemical shielding of the carbonyl groups, whose paramagnetic component is dominated by n = π* and π = π* excitations. Model compound calculations indicate that both the interaction energetics and the chemical shielding of the carbonyl group a...

15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) is an electrophilic lipid mediator derived from PGD2 with potent anti-inflammatory effects. These are likely to be due to the covalent modification of cellular proteins, via a reactive α,β-unsaturated carbonyl group in its cyclopentenone ring. This study was carried out to identify novel cellular target(s) for covalent modification by 15d-PGJ2 and to ...

The N-heterocyclic carbene catalyzed annulation of benzofuran-2,3-diones and enals via homoenolate intermediates is described. The reaction provided a direct and efficient method for the synthesis of spiro-bis-lactones. The ketone-carbonyl group annulated products and the ester-carbonyl group annulated products can be obtained as major products with good yields by convenient catalyst regulation...