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A convenient synthetic protocol for the construction of spiro[indoline‐3,3′‐quinoline]‐2,5′‐dione motifs was successfully developed by base promoted one‐pot three‐component reaction. In the presence of piperidine, three‐component reaction of ammonium acetate, aromatic aldehydes and the in situ generated 3‐isatyl 1,4‐dicarbonyl compounds, which were derived from base mediated addition of dimedone to 3‐methyleneoxindoles, resulted in two diastereoisomers of spiro[indoline‐3,3′‐quinoline]‐2,5′‐dione derivatives in good yields and with good diastereoselectivity. The stereochemistry of the reaction was clearly elucidated by isolation of two diastereomers and determination of several single crystal structures. [ABSTRACT FROM AUTHOR]

A series of the functionalised pillar[5]arene ureidopyrimidinone derivatives were successfully synthesised by the condensation reaction of mono-amido-functionalised pillar[5]arenes with 2-(1-Imidazolylcarbonylamino)-6-methyl-4-pyrimidinone in dry chloroform. 1H NMR, 2D NOESY spectra and single crystal structure clearly indicated that novel [1]rotaxanes were formed by insertion of longer alkylene chain into the cavities of the pillar[5]arenes. On the other hand, the ureidopyrimidinone-functionalised pillar[5]arenes tend to form the dimer in chloroform and in solid state through the self-complementary quadruple hydrogen bonding of the ureidopyrimidinone. [ABSTRACT FROM AUTHOR]

A series of novel functionalized p-tert-butyldihomooxacalix[4]arene mono-Schiff bases were conveniently synthesized by two-step reaction process. The synthetic rout included alkylation of p-tert-butyldihomooxacalix[4]arene with O-chloroalkoxy-substituted benzaldehydes and sequential condensation with 2-hydroxybenzohydrazide, 2-picolinohydrazideand aminothiourea. The single crystal structures of two p-tert-butyldihomooxacalix[4]arenederivatives were determined by X-ray single crystal diffraction method. The coordination abilities of dihomooxacalix[4]arene mono-Schiff bases towards transition metal ions were preliminarily investigated by UV-Vis spectra. [ABSTRACT FROM AUTHOR]

The base catalyzed aldol condensation of various N‐benzylisatins with 1‐acetyl‐N‐arylcyclopropanecarboxamides resulted in functionalized 3‐hydroxyoxindolin‐2‐ones in high yields, which were in turn successfully transferred to functionalized 6‐(2‐oxoindolin‐3‐yl)‐5‐azaspiro[2.4]heptanes in acetic acid in the presence of the concentrated hydrochloric acid by sequential acid catalyzed dehydration and aza‐Michael addition process. The 1H NMR spectra and the single crystal structure indicated that the obtained functionalized 6‐(2‐oxoindolin‐3‐yl)‐5‐azaspiro[2.4]heptanes have a S,S‐configuration. [ABSTRACT FROM AUTHOR]

A series of thiourea-functionalised pillar[5]arene derivatives3nmwere constructed from a series of mono-amide-functionalised pillar[5]arenes2n. The formation of their free forms or (pseudo)[1]rotaxane structures were controlled by their axle lengths or solvents, which were investigated by1H NMR spectroscopy. Some of (pseudo)[1]rotaxane structures were also supported by their single-crystal structures. [ABSTRACT FROM AUTHOR]

A series ofp-tert-butylcalix[4]arene 1,3-diimidazolium salts were successfully prepared by the alkylation ofp-tert-butylcalix[4]arene with dibromoalkanes, and sequential substitution reaction with 1-alkylimidazole. Furthermore, coordination reactions ofp-tert-butylcalix[4]arene 1,3-diimidazolium salts with silver oxide and mercury acetate gave novel Ag and Hg complexes of bis(N-heterocyclic carbenes) onp-tert-butylcalix[4]arene platform. The single-crystal structures of fourp-tert-butylcalix[4]arene 1,3-diimidazolium salts and three metal complexes were successfully determined by X-ray diffraction. An Ag–Ag argentophilic interaction (Ag–Ag bond length is 3.1599(6) Å) is formed between the two Ag–NHC complexes and a dimetallic coordination mode exists in Hg–NHC complexes. [ABSTRACT FROM PUBLISHER]

In poly[[μ3-2,2′-(disulfanediyl)dibenzoato-κ5 O: O, O′: O′′, O′′′](1,10-phenanthroline-κ2 N, N′)cadmium(II)], [Cd(C14H8O4S2)(C12H8N2)] n, the asymmetric unit contains one CdII cation, one 2,2′-(disulfanediyl)dibenzoate anion (denoted dtdb2−) and one 1,10-phenanthroline ligand (denoted phen). Each CdII centre is seven-coordinated by five O atoms of bridging/chelating carboxylate groups from three dtdb2− ligands and by two N atoms from one phen ligand, forming a distorted pentagonal-bipyramidal geometry. The CdII cations are bridged by dtdb2− anions to give a two-dimensional (4,4) layer. The layers are stacked to generate a three-dimensional supramolecular architecture via a combination of aromatic C-H...π and π-π interactions. The thermogravimetric and luminescence properties of this compound were also investigated. [ABSTRACT FROM AUTHOR]

The calix[4]arene-based podand which incorporates two terpyridine functions in 1,3-alternate positions with flexible propylene spacers at lower rim has been prepared and subjected to complexation studies with some transition metal ions. Single-crystal structures of Mn(II), Co(II), and Zn(II) complexes were determined by X-ray diffraction. These metal complexes are formed with a 2 : 1 ratio of metal and ligand. Coordination of each metal is five-coordinate distorted trigonal-bipyramidal geometry by three nitrogen atoms from a terpyridyl unit and two chloride atoms. [ABSTRACT FROM AUTHOR]

The calix[4]arene-based podand, which incorporates two Schiff-base functions derived from S-alkyldithiocarbazate in 1,3-alternate positions on the lower rim has been prepared and reacted with transition metal ions. X-ray single crystal diffraction of nickel and copper complexes shows that two iminothiolate domains are monoanionic bidentate planar chelators to coordinate one metal in distorted tetrahedral geometry. [ABSTRACT FROM AUTHOR]

The calix[4]arene-based podand which incorporates two salicylideneamine units in 1,3-alternate positions of the lower rim has been prepared and subjected to complexation studies with transition metal ions. The nickel and copper complexes form a 2 : 2 stoichiometric metallic macrocyclic framework. [ABSTRACT FROM AUTHOR]

A dicopper complex of p-tert-butylcalix8arene bearing eight salicylaldehyde acylhydrazone domains was prepared and its single crystal structure determined, in which only four acylhydrazone domains act as monoanionic tridentate planar chelators to coordinate to two copper ions. [ABSTRACT FROM AUTHOR]

Abstract: An efficient synthetic procedure for the complex dispirooxindoline fused [1,3]oxazines was successfully developed via Diels–Alder reaction of (E)-1,3-dihydro-3-phenacylidene-2H-indol-2-ones with 1,2-dihydro-2-oxospiro[3H-indole-3,2′-[2H,9aH-pyrido[2,1-b][1,3]oxazines], which were obtained from three-component reactions of pyridine and isatins with acetylenedicarboxylate or propiolate. 1H NMR data and single crystal structures indicated that this reaction has both high regioselectivity and diastereoselectivity. [Copyright &y& Elsevier]

Abstract: In the presence of FeCl3 as catalyst the one-pot domino reactions of arylamines, methyl propiolate, aromatic aldehydes, and indole in ethanol at room temperature proceeded smoothly to give methyl 2-(1H-indol-3-yl)arylmethyl-3-arylamino)acrylates in good yields. 1H NMR spectra and single crystal structures indicated that (Z)-acrylates were stereoselectively formed in the reactions. [Copyright &y& Elsevier]

A series of functionalized pillar[5]arenes mono-pyridylimine derivatives with different lengths of diaminoalkylene units as the side chains on the pillar[5]arene's rim were conveniently synthesized. The investigation of 1 H NMR spectra and single crystal structures indicated that the formation of free forms or pseudo[1]rotaxanes turned out to be controlled by both the axle lengths of diaminoalkylene chains and the solvent effect. The pillar[5]arene mono-pyridylimines with short hydrazinyl and diaminoethylene chains exist in free form. On the other hand, pillar[5]arene mono-pyridylimines with longer than diaminopropylene chains formed stable pseudo[1]rotaxanes both in solution and in the crystal state. [ABSTRACT FROM AUTHOR]

Calixarene-based compounds are highly effective therapeutic agents against cancer. This study aims to prepare a series of calix [n]arene (n = 4, 6, 8) polyhydroxyamine derivatives ( 3a–3m ) and to study their potential antitumor activities. The single crystal structure of calixs[4]arene derivative 3a was determined through X-ray diffraction. We assessed the ability of the prepared calix [n]arene polyhydroxyamine derivatives to induce cytotoxicity in six cancer cell lines by performing cancer cell growth inhibition assays. Results demonstrated that compounds 3a–3d achieved IC 50 values ranging from 1.6 μM to 11.3 μM. Among the different compounds, 3a and 3b exerted the strongest cytotoxic effect in inhibiting the growth of SKOV3 cells. In relation to the underlying mechanisms of cytotoxic effects, cell cycle analysis revealed that the exposure of SKOV3 cells to 3a induced cell cycle arrest in the G0/G1 phase, suggesting a reduction in DNA synthesis. Immunofluorescent staining indicated that the protein expression levels of caspase-3 and p53 in cells significantly increased, whereas that of Bcl-2 was effectively suppressed. Meanwhile, no significant changes in Bax were observed in SKOV3 cells. These results highlight that calixarene 3a can be further studied as a potential anticancer agent. [ABSTRACT FROM AUTHOR]

10α,20α-di(4-aminophenyl)calix[4]pyrroles were synthesized from the acid catalyzed cyclization of dialkyldipyrromethanes with p -nitroacetophenone and sequential hydrogenation of nitro group, which in turn reacted with several aromatic aldehydes and pyridinecarboxaldehydes as well as isocyanates to give a series of calix[4]pyrrole 10α,20α-disubstituted Schiff base and urea derivatives. The crystal structures of the newly-formed calix[4]pyrrole Schiff bases were successfully determined by X-ray diffraction. The complexing property of calix[4]pyrrole Schiff bases for transition metal ions was also investigated with UV–Vis spectroscopy. [ABSTRACT FROM AUTHOR]

Abstract: In the presence of methanesulfonic acid as catalyst, the condensation reactions of 5,5′-dialkyldipyrromethanes with p-hydroxyacetophenone in methanol resulted in a mixture of the unexpected polysubstituted 15α,20α-di(4-hydroxylphenyl)calix[4]pyrroles and the expected 10α,20β-di(4-hydroxylphenyl)calix[4]pyrroles in comparable lower yields. The crystal structures of the new calix[4]pyrroles and their oxyacetate derivatives were successfully determined by X-ray diffraction and the intermolecular interactions in the solid state is briefly discussed. [Copyright &y& Elsevier]

Abstract: Tetraaryl and tetraferrocenyl resorcinarenes 1a–1c have been synthesized by the HCl-catalyzed condensation of resorcinol with aromatic aldehydes or ferrocenecarbaldehyde, which were fully alkylated with ethyl α-chloroacetate to give the activated ethyl resorcinarylacetates 2a–2c. Reaction of 2a–2c with hydrated hydrazine yielded the resorcinarene acylhydrazine derivatives 3a–3c, from which the multi-ferrocenyl functional groups were selectively and efficiently introduced on the upper rim, or on the lower rim, or both on the upper and lower rims of resorcinarenes 4a–4c and calixarenes 4d–4f based upon the condensation reactions of acylhydrazones with ferrocenecarboxaldehyde. [Copyright &y& Elsevier]

A new potential tridentate ligand (H2L) was synthesized from condensation of ferrocenoylacetone (C5H5FeC5H4C(O)CH2C(O)CH3) with S-benzyldithiocarbazate in refluxing benzene. Reaction of the ligand (H2L) with a bivalent metal salt (M(OAc)2 · xH2O, M=Cu, Ni, Mn, Hg, Zn; SnCl2 · 2H2O) afforded the corresponding bivalent metal complexes M(HL)2 (I, M=Cu; II, M=Ni; III, M=Mn; IV, M=Hg; V, M=Zn; VI, M=Sn). All the new compounds have been characterized by elemental analyses, 1H NMR, IR and UV spectroscopies. A single-crystal X-ray analysis indicates that the ligand exists as a single iminone and not a tautomeric mixture of the iminone and enaminone. Crystallography of complex VI shows that the ligand acts as monoanionic tridentate coordinated to the tin atom via the carbonyl oxygen, deprotonated enamine nitrogen and thione sulfur atoms and the coordination geometry of the central metal is a distorted octahedron. [Copyright &y& Elsevier]