Chinese Journal of Chemistry最新文献

Monitoring and analyzing expression levels of multiple biomarkers in biological samples can improve disease risk prediction and guide precision medicine but suffers from high cost and being time-consuming. Here, we construct a fast molecular classifier based on freeze-thaw cycling that implements an in silico support vector machine (SVM) classifier model at the molecular level with a panel of disease-related biomarkers expression patterns for rapid disease diagnosis. The molecular classifier employs DNA reaction networks as the computing module and repeated dehydration and concentration process as the driving force to implement a set of simplified mathematical operations (such as multiplication, summation and subtraction) for efficient classification of complex input patterns. We demonstrate that the fast DNA-based molecular classifier enables precise cancer diagnosis within a short turnaround time in synthetic samples compared to those of free diffusion classifiers. We envision that this all-in-one molecular classifier will create more opportunities for inexpensive, accurate, and rapid disease diagnosis, prognosis and therapy, particularly in emergency departments or the point of care.

Dragocins A—C are structurally unique marine natural products featuring an uncommon tri-oxa-tricyclic[6.2.1]undecane moiety. However, their extremely low natural abundance has hindered extensive screening of their bioactivities. We hereby describe an efficient and modular approach to synthesizing dragocins A—C and their analogues using commercially available and inexpensive anisomycin and D-ribosyl thioglycoside derivative as the starting materials. A key feature of our synthesis is the construction of the uncommon tri-oxa-tricyclic[6.2.1]undecane skeleton. This challenging architecture is achieved by the stereocontrolled formation of the β-ribofuranosidic bond and the DDQ (2,3-dichloro-5,6-dicyano-1,4-benzoquinone)-promoted intramolecular cross-dehydrogenative etherification at the benzylic position. Our synthesis is also characterized by the successful installation of a chlorine atom and a methoxy group at the tertiary C-4' position via a late-stage silver-catalyzed decarboxylative chlorination reaction and an electrophilic etherification reaction of the enol intermediate. Cytotoxicity evaluations of the synthesized compounds revealed demethyl dragocin A, the N-demethylated derivative of dragocin A, as a potential anticancer candidate due to its strong cytotoxicity against A549 lung, HCT116 colorectal and MCF7 breast cancer cell lines. This work also demonstrated the preliminary structure-activity relationship of this compound, setting a solid foundation for developing novel anticancer candidates.

A regioselective C8−H alkylation of polyaromatics exampled with inert alkyl chloride is reported. The reaction proceeds via the synergistic participation of inexpensive transition metals nickel and cobalt. This approach enables the coupling of various substituted polyaromatic rings with a broad range of primary and secondary alkyl chlorides. Further synthetic applications provide a series of simple conversions to useful building blocks, suggesting its potency in the late-stage functionalization of complex molecules. Mechanistic investigation illustrates that the reaction goes through a radical process with an unusual Ni(II)→Ni(III)→Ni(I) cycle being responsible for the rate-determining C−H insertion of alkyl radicals, which are generated by the homolysis of chloroalkane with 2-electrons oxidative addition of Co(I).

Organic-inorganic hybrid perovskites (OIHPs) offer precise control over material properties through the substitution of organic cations and halogens. In this study, two OIHPs, [(C₆H₁₀P)(n-BA)]Sb₂X₉ ([C₆H₁₀P]⁺ = [Me₃PCH₂CH₂CH₃]⁺, [n-BA]⁺ = n-butylamine cation, X = I (1), Br (2)), were synthesized by varying halogens within a mixed-cation system. The halogen substitution induced a shift from compound 1, which remains stable without phase transitions, to compound 2, which undergoes a ferroelastic phase transition (mmmF2/m). Compound 1 crystallizes in the non-centrosymmetric Pca2₁ space group and demonstrates a second harmonic generation (SHG) response, while compound 2 displays elasticity in nanoindentation tests. Halogen substitution alters Sb—X bond lengths, inducing structural distortions in the inorganic framework and influencing the spatial configuration of organic cations and inorganic anions. These changes lead to distinct crystallization behaviors, resulting in different physical properties for compounds 1 and 2. This work contributes to the development of multifunctional materials based on halogen regulation in mixed-cation OIHPs.

The development of sustainable and efficient catalytic systems for the formation C—C, C—N, C—O bonds is a fundamental goal in modern synthetic chemistry. We present a biomass-derived Cu/Chitosan-800 catalyst that facilitates a range of carbenoid insertion reactions into C—H, N—H, and O—H bonds. This catalyst demonstrates remarkable activity, enabling the functionalization of diverse substrates, including the late-stage modification of drug molecules with up to 95% yield and good recyclability. Our findings highlight the catalyst's potential in advancing environmentally friendly chemical transformations, offering a promising tool for pharmaceutical synthesis and organic synthesis.

Chiral perovskites provide an ideal platform for the construction of linear and nonlinear optical materials due to their diverse chemical variability, structural tunability, and intrinsic non-centrosymmetricity which have broad application prospects for next-generation optoelectronic devices. In this work, a pair of 1D chiral lead halide perovskites (R/S-4MeOPEA)PbCl₃ (4MeOPEA = (4-methoxyphenyl)ethylamine) were synthesized, and characterized systematically. Crystal structure analysis revealed that the one-dimensional (1D) inorganic chain formed by face-shared lead chloride octahedra was separated by the chiral organic spacers. The distorted octahedra endows them with broadband bluish-white light emission centered covering the range 350—700 nm with a width of 104 nm. In addition, the highly anisotropic second-harmonic generation (SHG) with a near unity polarization ratio was observed. This work presents a fresh example of 1D chiral perovskite with exotic linear and nonlinear optical properties, which could provide a new footstone for further optoelectronic devices.

An atmospheric-oxygen-mediated four-component reaction was developed for the divergent synthesis of pyrazolo[1,5-a]pyrimidine and pyrazolo[3,4-b]pyridine derivatives from readily available alcohols and 3-aminopyrazoles. In this transformation, atmospheric oxygen serves as the green oxidant, promoting alcohols as equivalent aldehydes for the synthesis of four types of N-containing heterocycles (> 40 examples). Remarkably, the transformation features metal-free and molecular diversity.

A series of sulfonatopropoxylated cucurbit[8]uril derivatives (SPECB8s) with water-solubility ranging from 344 mmol/L to 360 mmol/L have been prepared. One of the derivatives SPE_5.5CB8 bearing an average of 5.5 sulfonatopropoxy side chains has been revealed to display high biocompatibility, with maximum tolerated dose being as high as 2500 mg/kg for mice. Phase solubility diagram investigations illustrate that SPE_5.5CB8 can solubilize eighteen poorly soluble drugs and, for fifteen of them including remdesivir, its solubilization efficiency is higher than that of Captisol, the most widely used β-cyclodextrin-derived excipient for drug formulation. Moreover, the improved solubilization for remdesivir, which is formulated by Captisol for clinical use, can lead to important increase of its antiviral activity as compared with Captisol.