The title compound, C(35)H(36)N(4)O(4), was prepared as a spiro-lactam ring formation of rhodamine B dye for comparison with a ring-opened form. The xanthene ring system is approximately planar. The r.m.s. deviation from planarity is 0.064 (6) Å for the xanthene ring. The dihedral angles formed by the spiro-lactam and 2,4-dihydroxy-benzene rings with the xanthene ring system are 86.6 (9) and 88...

The title compound, C(36)H(36)N(4)O(4), was prepared as a spiro-lactam ring formation of the rhodamine dye for comparison with a ring-opened form. The xanthene ring system is approximately planar [r.m.s. deviations from planarity = 0.023 (9) Å for the xanthene ring]. The dihedral angles formed by the spiro-lactam and 1,3-benzodioxole rings with the xanthene ring system are 86.8 (1) and 74.3 (1)...

A six-membered N-heterocyclic carbene fused with a spiro-scaffold is designed. The new NHC shows stronger σ-donation ability than typical 5-membered NHCs. This property leads to interesting reactivities of this spiro-fused six-membered NHC. For example, the NHC-BF3 Lewis pair complex can be readily prepared by using LiBF4 as the BF3 source, or through a direct bond-reconstruction of the tetrafl...

Inhibition of the MDM2-p53 protein-protein interaction is being actively pursued as a new anticancer therapeutic strategy, and spiro-oxindoles have been designed as a class of potent and efficacious small-molecule inhibitors of this interaction (MDM2 inhibitors). Our previous study showed that some of our first-generation spiro-oxindoles undergo a reversible ring-opening-cyclization reaction th...

spiro-4- thiazolidinones have been synthesized by the cyclocondensation of phthalazinyl hydrazones with cyclic ketones and substituted mercapto acetic acids. compounds were screened for their antibacterial, antifungal and antihypertensive activity. the combined elemental analyses and spectroscopic data prove the authenticity of the synthesized compounds

A new Pd-catalyzed reaction for the stereoselective synthesis of cyclopentane-fused benzocyclobutenes is described. These transformations likely proceed via carbamate-directed carbopalladation followed by intramolecular C-H activation of an alkylpalladium intermediate. The mechanistic relationship between these transformations and Pd-catalyzed reactions of gamma-(n-Boc-amino)alkenes with aryl b...

This article presents the synthesis of new derivatives of spirooxindole-spiropiperidinone- pyrrolidines 6a-j and spirooxindole-spiropiperidinone-pyrrolizines 8a-j, through a 1,3-dipolar cycloaddition reaction of azomethineylides generated from isatin, sarcosine, and l-proline, through a decarboxylative route with dipolarophile 4a-j. All of the newly synthesized compounds were evaluated for thei...

An efficient and practical approach for the synthesis of all four stereoisomers of the MT(2) melatonin receptor ligand 4-phenyl-2-propionamidotetralin (4-P-PDOT), each in enantiomerically pure form (ee > 99.9%), was developed. The strategy involved an optical resolution procedure of the key precursor (±)-4-phenyl-2-tetralone with the unusual resolving agent (S)-mandelamide, through the formatio...

In this paper, the pore filling of spiro-OMeTAD (2,2(,7,7(-tetrakis-(N,N-di-pmethoxyphenylamine)9,9(-spirobifluorene) in mesoporous TiO2 films is quantified for the first time using XPS depth profiling and UV–Vis absorption spectroscopy. It is shown that spiro-OMeTAD can penetrate the entire depth of the film, and its concentration is constant throughout the film. We determine that in a 2.5-mm-...

This Focus Review highlights the exciting results obtained in the area of asymmetric catalysis using spirobiindane- or spirobifluorene-based chiral ligands. The spiro, mono, and bidentate ligands have been successfully applied in a wide range of transition-metal-catalyzed asymmetric reactions, including hydrogenations, carbon-carbon and carbon-heteroatom coupling reactions, with superior or com...