Publications by authors named "Qing-lan Zhao"

Divergent synthesis provides an indispensable route to rapid acquisition of structurally diverse chemical scaffolds from identical starting materials. Herein, we describe unprecedented divergent annulations of -hydroxyarylenaminones promoted by -butyl nitrite (TBN) under mild conditions. Two different types of benzo--heterocycle, including oximinochromanones and oximinocoumaranones, were smoothly assembled with a broad substrate scope and good functional group compatibility.

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Acyl oximes are directly used as the acyl radical precursors in the hydroacylation reactions for the first time. In this work, acyl radicals can be effectively generated -scission of a phosphoranyl radical under photocatalytic conditions. As a result, the hydroacylation of alkenes triggered by the resulting acyl radicals leads to facile syntheses of a range of valuable ketones.

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One-pot ring-opening/ring-closure process of combining methyleneindolinone with 3-aminooxindole has been developed in this work. Novel polycyclic spirooxindoles were efficiently assembled under mild conditions in high yields (up to 95 %) with moderate to good diastereoselectivities (up to >95:5 d.r.

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A facile and enantioselective access to a functionalized octahydroacridine scaffold was developed via an organocatalytic domino sequence between cyclohexenone and 2- N-substituted benzaldehyde. High levels of yields (up to 99%) and enantioselectivities (up to 99:1 er) were readily achieved in this developed organocatalytic transformation, which holds promising applications in the construction of complex multicyclic systems for further pharmacological studies.

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A facile and diversified synthesis of functionalized CF-containing benzoxepine derivatives via photoredox catalysis was achieved in this work. This novel protocol features broad substrate scope, mild reaction conditions, operational simplicity, easy scale-up, and versatile derivatization, which would facilitate its practical and broad applications in the construction of valuable and synthetically challenging heterocycles.

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An efficient and diastereoselective decarboxylative oxa-1,3-dipolar cycloaddition between 3-oxindoles and diverse amino acids is developed to access novel oxazolidine-dispirooxindole skeletons bearing vicinal quaternary carbon centers. This protocol features operational simplicity, a broad substrate scope, and good to excellent chemical yields and diastereoselectivities. In particular, minimal solvent (1 mL/10 mmol) and chromatography-free purification render this synthetic process more efficient and environmentally benign in the context of green chemistry.

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With the aid of in situ protection by N-(2-formylphenyl)-4-methyl-benzenesulfonamide, enantioselective allylic alkylation of Morita-Baylis-Hillman carbonates with diethyl 2-aminomalonate was successfully realized. The corresponding adducts can be obtained in up to 99% yield with up to 98% ee as well as excellent regioselectivity. Besides, the adducts with opposite configurations were readily prepared by utilizing easily available and inexpensive quinine or quinidine as organocatalyst.

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A diversity-driven three-component 1,3-dipolar cycloaddition of isatins, amino acids and isatin-derived ketimines was developed to facilely assemble dispirooxindole-imidazolidine skeletons bearing vicinal quaternary carbon centers. This protocol features additive-free, minimal solvent usage (0.1 mL DMSO/0.

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Both tumor suppressor and tumor promoter roles, which are dependent on the tumor type, have been described for caveolin-1 (CAV-1). Because CAV-1 can modulate cell signaling, we tested the hypothesis that it regulates lung adenocarcinoma cell proliferation and metastasis via modulation of epidermal growth factor receptor (EGFR) activity. The lung adenocarcinoma cell line, GLC-82, was transfected with pcDNA3.

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The asymmetric unit of the title compound, [Zn(C(12)H(12)N(2))(H(2)O)(4)]SO(4), consists of a Zn(II) complex cation, a sulfate anion and four mol-ecules of water coordinated to the Zn(II) atom. The Zn(II) complex cation, with approximate twofold symmetry, displays a slightly distorted octa-hedral geometry around the Zn(II) atom, which is coordinated by two N atoms from a 5,5'-dimethyl-2,2'-bipyridine ligand and by the O atoms of four water mol-ecules. In the crystal, O-H⋯O hydrogen bonds help to establish the packing.

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Dibromido(2,2':6',2''-terpyridine-κN,N',N'')zinc(II).

Acta Crystallogr Sect E Struct Rep Online

May 2009

In the title compound, [ZnBr(2)(C(15)H(11)N(3))], the Zn(II) ion is five-coordinated by the three N atoms from a 2,2':6',2''-terpyridine ligand (terpy) and two bromide anions in a distorted trigonal bipyramidal configuration. Each mol-ecule is situated on a twofold rotational axis that passes through the Zn(II) ion and the central ring of the terpy ligand. In the crystal structure, aromatic π-π inter-actions between terpy ligands [centroid-centroid distances = 3.

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Objective: To study the location, treatment, life status of multiple primary cancers (MPCs) in head and neck squamous cell carcinomas.

Methods: The clinical data of 71 head and neck squamous carcinoma patients with MPCs were retrospectively analyzed.

Results: MPCs were seen in head and neck regions in 27 cases and in remote organs in 42 cases, two of which were triplicate primary cancers.

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