Copper-Mediated Radical-Induced Ring-Opening Relay Cascade Carboannulation Reaction of [60]Fullerene with Cyclobutanone Oxime Esters: Access to [60]Fullerene-Fused Cyclopentanes.

An unexpected copper-mediated radical-induced ring-opening relay cascade carboannulation reaction of [60]fullerene with cyclobutanone oxime esters is presented for the preparation of various Cl-/Br-incorporated [60]fullerene-fused cyclopentanes. The unique relay cascade transformation uses inexpensive copper salts as promoters and halogen sources and features simple redox-neutral conditions and a broad substrate scope, providing a practical access to a class of novel five-membered carbocycle-fused fullerenes.

Acid-Responsive Dissociation of Ferrocene Compounds: Diels-Alder Diene Equivalents for Selective Preparation of [60]Fullerene-Fused Bicyclo[2.2.1]hept-5-enes.

Herein, an unprecedented transformation of [60]fullerene with ferrocene compounds giving access to various [60]fullerene-fused bicyclo[2.2.1]hept-5-enes is presented. In the presence of an acid, ferrocene compounds undergo an unusual dissociation process and serve as Diels-Alder diene equivalents to react with [60]fullerene for the selective construction of a class of novel fullerene-fused bridged carbocyclic derivatives. The reaction is easy to perform and has a wide substrate scope as well as excellent functional group compatibility, representing a new application of ferrocene compounds in synthetic chemistry.

Broad Synthesis of Disubstituted Dihydrofuran-Fused [60]Fullerene Derivatives via Cu(I)/Ag(I)-Mediated Synergistic Annulation Reaction.

A novel and efficient Cu(I)/Ag(I)-mediated synergistic annulation reaction of [60]fullerene with diarylethanones, benzoylacetonitriles, and ß-dicarbonyl compounds has been developed for the direct construction of diverse disubstituted dihydrofuran-fused [60]fullerene derivatives. This transformation exhibits a remarkably broad substrate scope and functional group tolerance and provides a useful method to a scarce class of fullerene derivatives.

Wnt/ß-catenin signaling plays an important role in the protective effects of FDP-Sr against oxidative stress induced apoptosis in MC3T3-E1 cell.

Strontium fructose 1,6-diphosphate (FDP-Sr) is a new strontium-containing compound. The primary aim of this study was to clarify whether the structure component of FDP-Sr, FDP could benefit the protective effect of Sr (II) against oxidative stress induced apoptosis, and meanwhile to further explore the important role of Wnt/ß-catenin signaling in the anti-apoptosis effect of FDP-Sr in response to oxidative stress induced by H2O2 in an osteoblastic MC3T3-E1 cell line. Results showed that FDP-Sr could improve the osteoblastic differentiation under oxidative stress with induced cell proliferation and improved mineralization. The inhibition effect of FDP-Sr on cell apoptosis induced by H2O2 was proved by reduced reactive oxygen species production and activated caspase3. Under oxidative stress, mRNA and protein levels of phospho-ß-catenin reduced, while ß-catenin increased in the FDP-Sr treatment cell, leaded to the up-regulations of Runx2 and OPG at both mRNA and protein levels, finally improved the differentiation of osteoblasts. By the engagement of Wnt/ß-catenin pathway's inhibitor (XAV-939), the protective effects of FDP-Sr on osteoblastic differentiation against oxidative stress were repressed along with inhibited wnt/ß-catenin signaling and reduced mRNA and protein levels of Runx2 and OPG. In conclusion, FDP-Sr was demonstrated to protect osteoblast differentiation from oxidative damage induced by H2O2 through up-regulation of Wnt/ß-catenin signaling, and FDP in FDP-Sr was able to directly improve the oxidative stress injury through its ROS scavenging ability.

Iron-mediated internal-oxidant relay cascade reaction: strategy to synthesize fullerenooxazoles and hydroxyfullerenyl amides.

A novel FeCl2·4H2O-mediated internal-oxidant relay cascade reaction has been developed by functionalization of O-substituted benzohydroxamic acids or N-chloro-arylamides with [60]fullerene. Depending on the nature of the N-substituted groups, fullerenooxazoles or rare hydroxyfullerenyl amides could be obtained in a straightforward and flexible manner. Such a new transformation provides a unique strategy for the synthesis of fullerenooxazoles or hydroxyfullerenyl amides.

Interrupted N-Heterocyclic Carbene-Catalyzed Radical Coupling Strategy: A Versatile Platform for Alkylation and Arylation of [60]Fullerene.

An interrupted N-heterocyclic carbene-catalyzed radical coupling strategy is disclosed for efficient alkylation and arylation of [60]fullerene. This novel and general strategy bridges the gap between organocatalytic radical cross-coupling and functionalization of fullerenes. Readily available feedstocks, remarkably broad substrate scope and functional group compatibility, and convenient late-stage nanomodification of complex molecules make this strategy with incomparable diversity and practicality in the synthesis of monoalkylated and -arylated fullerenes.

Catalytic System-Controlled Regioselective 1,2- and 1,4-Carboannulations of [60]Fullerene.

Selective functionalization of fullerenes is an important but challenging topic in fullerene chemistry and synthetic chemistry. Here we present the first example of catalytic system-controlled regioselective 1,2- and 1,4-addition reactions for the flexible and efficient synthesis of novel 1,2- and 1,4-carbocycle-fused fullerenes via a palladium-catalyzed decarboxylative carboannulation process.

Solvent-free synthesis of zeolites from solid raw materials.

As important industrial materials, microporous zeolites are necessarily synthesized in the presence of solvents such as in hydrothermal, solvothermal, and ionothermal routes. We demonstrate here a simple and generalized solvent-free route for synthesizing various types of zeolites by mixing, grinding, and heating solid raw materials. Compared with conventional hydrothermal route, the avoidance of solvents in the synthesis not only significantly reduces the waste production, but also greatly increases the yield of zeolite products. In addition, the use of starting solid raw materials remarkably enhances the synthesis efficiency and reduces the use of raw materials, energy, and costs.

Assembly of Diverse [60]Fullerene-Fused Tricyclic Scaffolds via a Palladium-Catalyzed Cascade [2 + 2 + 2] Annulation Reaction.

Herein, a concise and robust approach for the highly efficient assembly of [60]fullerene-fused tricyclic scaffolds has been developed through a palladium-catalyzed cascade [2 + 2 + 2] annulation process. Diverse tricyclic scaffolds incorporating various ring sizes (6-19 membered) and types (carbocycles and N- and O-heterocycles) can be expediently constructed in a single-step transformation.

NHC-Catalyzed Three-Component Hydroalkylation Reactions of [60]Fullerene: An Umpolung Approach to Diverse Monoalkylated Hydrofullerenes.

A novel N-heterocyclic carbene-catalyzed three-component umpolung hydroalkylation of [60]fullerene with 4-(chloromethyl)-benzaldehydes/α,ß-unsaturated aldehydes and alcohols/thioalcohols has been developed for the flexible and efficient preparation of diverse monoalkylated hydrofullerenes. Organic catalysis, broad substrate scope, excellent functional group tolerance, and products with high diversity and complexity levels are attractive features of this protocol.

Fabrication of synergistic sites on an oxygen-rich covalent organic framework for efficient removal of Cd(II) and Pb(II) from water.

A key matter in heavy metal removal technology is to develop the adsorbents with efficient adsorption sites. In this study, an oxygen-rich covalent organic framework (JUC-505) was functionalized by carboxyl (-COOH) groups to form synergetic effects aiming for the removal of Cd(II) and Pb(II) ions. JUC-505-COOH shows a high Cd(II) uptake of 504 mg⋅g-1 surpassing most of the reported porous adsorbents. Meanwhile, the kinetics study shows a rapid adsorption process at a high initial concentration (100 mg⋅L-1), and the equilibrium can be reached within 5 min. We investigated the adsorption mechanism in-depth by density functional theory calculations, proving the synergistic effects of surface complexation and hydrogen-bond, which are from the post-modified -COOH groups and the in-situ oxygen atoms of JUC-505, respectively. Moreover, under the interference of common ions in natural water, the removal efficiency of Cd(II) is almost insusceptible, which sheds lights on the potential for the application in the natural water purification. In addition, the Pb(II) uptake (559 mg⋅g-1) and the adsorption kinetics also surpass most of the reported porous adsorbents.

Metal-Free-Catalyzed Three-Component [2+2+2] Annulation Reaction of [60]Fullerene, Ketones, and Indoles: Access to Diverse [60]Fullerene-Fused 1,2-Tetrahydrocarbazoles.

The first example of metal-free-catalyzed multicomponent annulation reaction of [60]fullerene has been developed for concise and efficient construction of novel [60]fullerene-fused 1,2-tetrahydrocarbazoles. Using inexpensive and readily available I2 as a catalyst, [60]fullerene, ketones, and indoles undergo a formal [2+2+2] annulation process to conveniently assemble diverse 1,2-tetrahydrocarbazoles. Mechanistic studies indicate that this reaction proceeds through I2-promoted generation of a 3-vinylindole structure with the characteristics of a conjugated diene followed by cycloaddition to [60]fullerene.

Palladium-catalyzed domino spirocyclization of [60]fullerene: synthesis of diverse [60]fullerene-fused spiro[4,5]/[5,5] derivatives.

Herein a new, general and practical method for the spirocyclization of [60]fullerene through a palladium-catalyzed domino Heck/C-H activation reaction is presented. A wide range of novel [60]fullerene-fused spirocyclic derivatives can be easily and flexibly synthesized with a broad substrate scope and excellent functional-group tolerance. A plausible mechanism involving an alkyl Pd(ii) species as a key intermediate has been proposed.

Iron-Catalyzed Redox-Neutral Radical Cascade Reaction of [60]Fullerene with γ,δ-Unsaturated Oxime Esters: Preparation of Free (N-H) Pyrrolidino[2',3':1,2]fullerenes.

Herein an unprecedented iron(II)-catalyzed redox-neutral radical cascade reaction of [60]fullerene with γ,δ-unsaturated oxime esters is reported for the preparation of novel free (N-H) pyrrolidino[2',3':1,2]fullerenes. The transformation undergoes an intramolecular cyclization/intermolecular cyclization/oxidation/hydrolysis cascade, and features simple operation, broad substrate scope/high functional group compatibility as well as suitable for scale-up synthesis, providing a facile and practical access to a range of free pyrrolidino[2',3':1,2]fullerenes.

Ordered cubic mesoporous silicas with large pore sizes synthesized via high-temperature route.

Ordered cubic mesoporous silicas with large pore sizes (LP-SBA-16) have been successfully synthesized at high temperatures (180-220 degrees C) using polymer surfactant of F127 as a template. Compared with conventional SBA-16 with entrance size at 3.6 nm, LP-SBA-16 samples synthesized at high temperatures show large entrance sizes at 11.8-24.7 nm, confirmed by the pore size distribution and TEM images. The formation of these large pore sizes in the samples is attributed to the increase of surfactant hydrophobicity and the merging of mesopores at high temperatures. The results obtained from NMR and XRD techniques show that ordered mesostructure in LP-SBA-16 samples basically remained even if the surfactant (F127) is fully decomposed at high temperatures, indicating that F127 surfactant becomes unimportant when the mesoporous walls of silica have been condensed. Furthermore, we have compared the adsorption capacity of myoglobin over conventional SBA-16 and LP-SBA-16 samples, and it is found that LP-SBA-16 samples exhibit much higher adsorption capacity than conventional SBA-16, which is potentially important for immobilization of enzymes on ordered mesoporous materials.

Copper-Catalyzed N-H/C-H Sequential Relay Oxidative Radical Carboannulation: Construction of Diversely Substituted [60]Fullerene-Fused Tetrahydrocyclopenta[b]indoles.

Reported herein is a new copper-catalyzed N-H/C-H sequential relay oxidative radical carboannulation of [60]fullerene with C2-functionalized free indoles for the direct construction of novel [60]fullerene-fused tetrahydrocyclopenta[b]indoles. The transformation shows high regioselectivity and atom economy, broad substrate scope, and good functional group tolerance, providing an efficient and practical approach to access diversely substituted fullerene-fused polycyclic derivatives from simple hydrocarbons.

Association between metabolic profiles in urine and bone mineral density of pre- and postmenopausal Chinese women.

OBJECTIVE: In the present study, we aimed to characterize the pathological development of menopausal osteoporosis, as well as to explore potential biomarkers and metabolic pathways involved in osteoporosis. METHODS: Urine samples from 322 female participants categorized by menopause status and different bone conditions were collected and analyzed based on a gas chromatography-mass spectrometry (GC-MS) approach. Multivariate and univariate statistical analyses were carried out for urinary metabolomic profile characterization and comparison. RESULTS: Seventeen metabolites in the low bone mineral density (BMD) groups were clearly differentiated from those in normal BMD groups. Among these 17 differentiating metabolites, taurine, ß-alanine, and 5-hydroxycaproic acid were found to be potential biomarkers of osteoporosis. The taurine metabolic pathway and the ß-alanine metabolic pathway were found to be related to menopause and bone loss. CONCLUSIONS: Based on the GC-MS metabolomic platform, four typical pathological phases during the progression of postmenopausal osteoporosis were described. Several differentiating metabolites and metabolic pathways were found to be closely related to the pathology of postmenopausal osteoporosis. Our results provided a solid foundation for further studies on early diagnosis and pathomechanistic evaluation.

N-Heterocyclic Carbene-Catalyzed α,ß-Unsaturated Aldehydes Umpolung in Fullerene Chemistry: Construction of [60]Fullerene-Fused Cyclopentan-1-ones and Cyclohex-2-en-1-ones.

The first umpolung strategy for the cycloacylation of fullerene using a N-heterocyclic carbene organocatalyst is reported. The coupling of [60]fullerene with different structural α,ß-unsaturated aldehydes efficiently furnishes interesting [60]fullerene-fused cyclopentan-1-ones or cyclohex-2-en-1-ones in good to excellent yields. This new reaction displays a wide substrate scope and excellent functional-group tolerance, and diverse substituents such as aryl, heteroaryl, alkenyl, alkyl, and ester can be installed by using the corresponding enals.

Solvent-promoted catalyst-free regioselective N-incorporation multicomponent domino reaction: rapid assembly of π-functionalized [60]fullerene-fused dihydrocarbolines.

Described here is the first example of solvent-promoted catalyst-free N-incorporation multicomponent domino reaction for the direct construction of novel π-extension [60]fullerene-fused dihydrocarbolines from simple hydrocarbons. This unprecedented transformation is proposed to proceed by a sequential N-incorporation/[4+2] cycloaddition/elimination process, involving multiple types of bond cleavage and formation in a single chemical operation. Mechanistic studies uncover that solvent is crucial for the success of the transformation, and multiple solvent-aided deprotonation and proton transfer are involved as key steps.

Association between the metabolome and bone mineral density in pre- and post-menopausal Chinese women using GC-MS.

The present study describes for the first time, a metabolic profile reflecting the osteoporosis progression in 364 pre- and postmenopausal Chinese women using GC-MS. In order to accurately evaluate the dynamic changes of metabolites along with estrogen deficiency and osteoporosis progression, we divided these subjects into the following four groups: premenopausal women with normal bone mass density (BMD, group I), postmenopausal women with normal BMD (group II), postmenopausal women with osteopenia (group III) and postmenopausal women with osteoporosis (group IV), according to their menopause or low BMD status. Principal component analysis (PCA) and Partial least squares-discriminant analysis (PLS-DA) were used to evaluate the associations of metabolic changes with low BMD or estrogen deficiency. Twelve metabolites identified by the PLS-DA model were found to be able to differentiate low BMD groups from normal BMD groups. Of the 12 metabolites, five free fatty acids (LA, oleic acid, AA and 11,14-eicosadienoic acid) have the most potential to be used as osteoporosis biomarkers due to their better correlations with BMD, and high sensitivity and specificity in distinguishing the low BMD groups from the normal BMD groups calculated by the receiver operating characteristic curve (ROC). The lipid profile may be useful for osteoporosis prediction and diagnosis.