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Background: Pulmonary hypertension (PH) is common in patients with end-stage renal disease (ESRD). Arteriovenous fistulas (AVF) creation may involve in the pathogenesis of PH. The aim of this study was to explore the impact of PH after AVF creation on the AVF failure rate in maintenance hemodialysis (MHD) patients. Methods: From January 1, 2009, to January 1, 2019, we retrospectively collected data of 578 MHD patients in Guangdong Provincial People’s Hospital Blood Purification Center, China. Patients were followed-up until AVF failure or death or May 25, 2020. According to the systolic pulmonary artery pressure (SPAP) within 1 year after the establishment of AVF, the MHD patients were divided into three groups: SPAP ⩽ 35 mmHg, 35 Results: A total of 578 patients were analyzed. The average age was 60.66 ± 15.34 years (58.1% men). Of these, 26.1% of patients were reported PH. The SPAP exhibited a left-skewed nonparametric distribution and the overall SPAP after the creation of AVF was 39.00 (29.00–52.00) mmHg. The median follow-up was 5.8 (5.5–6.3) years. Overall, 12.8% (74/578) patients were reported AVF failure events. There was no significant difference in AVF failure rate among three groups ( p = 0.070). A total of 111 (19.2%) died during the follow-up period. Compared with the SPAP ⩽35 mmHg group, only the all-cause death rate significantly increased in MHD patients with PH ( p Conclusions: The secondary pulmonary hypertension after AVF creation did not increase the risk of AVF failure in MHD patients, but significantly increased the risk of mortality for this portion of the patients. Future larger sample sizes, multi-center, and prospective trials are needed to make sure which type of access will benefit on their survival for MHD patients with SPAP ⩾35 mmHg.

An I2-mediated annulation of 2-amino[1,3,5]triazines and ketones for the synthesis of imidazo[1,2-a][1,3,5]triazines is presented. Electron rich, or electron poor acetophenone and heterocycle ketones, as well as propiophenone, are functionalized with 2-amino-[1,3,5]triazines. Another class of imidazo[1,2-a][1,3,5]triazines tethered with an additional 1,2-dicarbonyl motif through the combination of annulation and C–H functionalization were obtained instead by changing the reaction conditions. The new methods are practically straightforward and applicable on a gram scale.

An efficient ruthenium-catalyzed N-alkylation of amino 1,3,5-triazines with alcohols was achieved via a BH/HA strategy. Following this simple, facile, and high atom economical protocol, a broad range of products was prepared in moderate to good yields and heterocyclic or benzylic alcohols containing various functionalities were tolerated. The application of the reaction is also further demonstrated by the synthesis of alkylated secondary amine-1,3,5-triazines from olefinated amino-1,3,5-triazines and alcohols via a one pot N-alkylation and reductive reactions.

Aroylimidazo[1,2-a][1,3,5]triazines are rapidly synthesized via a facile and mild reaction of 2-amino-triazines and 1,3-dicarbonyl compounds using NBS. The reaction occurred with good yields and excellent regioselectivity, and β-keto esters, β-keto amides, and 1,3-diones were tolerated under the optimized procedure. In addition, the successful application of this methodology for a gram-scale reaction indicates its potential for bulk synthesis.

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An efficient Cs2CO3-promoted synthesis of acylated p-terphenyls from allylic ketones under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated γ-aryl substituted allylic aryl ketones containing functionalities such as alkanes, ethers and halogens. Keywords: Cs2CO3, p-Terphenyls, Allylic ketone, Synthesis

An efficient copper-catalyzed synthesis of pyrazolo[5,1-a]isoquinolines from 2-gem-dipyrazolylvinylbromobenzenes under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated nitrile, ether, and halogen substituted 2-gem-dipyrazolylvinylbromobenzenes.

Copper-catalyzed intermolecular annulation of 2-amine-[1,3,5]triazines and aryl nitriles for the synthesis of [1,2,4]triazolo[1,5- a][1,3,5]triazines via N-C bond formation and oxidative N-N coupling [oxidative 3 + 2 cyclization] is presented. A wide range of aryl nitriles, including electron-rich benzonitriles, electron-poor benzonitriles, 2-cyanothiophene, and 4-cyanopyridine, were all functionalized with 2-amine-[1,3,5]triazines. Furthermore, amidation of 2-amine-[1,3,5]triazines via Cu-catalyzed C-CN bond cleavage of phenylacetonitriles is also demonstrated. The reaction occurred in moderate to satisfactory yields and tolerated alkyl- or aryl-substituted 2-amine-[1,3,5]triazines. Aniline, aminopyridine, and aminopyrimidine also afforded the desired products.

Background Brain amyloid deposition is one of the main pathological characteristics of Alzheimer’s disease (AD). Soluble oligomers formed during the process that causes β-amyloid (Aβ) to aggregate into plaques are considered to have major neurotoxicity. Currently, drug development for the treatment of Alzheimer’s disease has encountered serious difficulties. Our newly proposed solution is to accelerate the aggregation of Aβ to reduce the amount of cytotoxic Aβ oligomers in brain tissue. This strategy differs from the existing strategy of reducing the total Aβ content and the number of amyloid plaques. Method In this study, we screened a small library and found that a flavonoid compound (ZGM1) promoted the aggregation of β-amyloid (Aβ). We further verified the binding of ZGM1 to Aβ42 using a microscale thermophoresis (MST) assay. Subsequently, we used dot blotting (DB), transmission electron microscopy (TEM), and thioflavin T fluorescence (ThT) measurements to study the aggregation of Aβ under the influence of ZGM1. By using cell experiments, we determined whether ZGM1 can inhibit the cytotoxicity of Aβ. Finally, we studied the protective effects of ZGM1 on cognitive function in APPswe/PS1 mice via behavioral experiments and measured the number of plaques in the mouse brain by thioflavin staining. Results ZGM1 can bind with Aβ directly and mediate a new Aβ assembly process to form reticular aggregates and reduce the amount of Aβ oligomers. Animal experiments showed that ZGM1 can significantly improve cognitive dysfunction and that Aβ plaque deposition in the brain tissue of mice in the drug-administered group was significantly increased. Conclusion Our research suggests that promoting Aβ aggregation is a promising treatment method for AD and deserves further investigation.

An efficient synthetic pathway for the total synthesis of salvianolic acid N has been reported. The key reaction steps, the Wittig reaction for Z-stereoselectivity and an intramolecular cyclization for a seven membered ring skeleton, have been optimized to improve the synthetic feasibility and provide the best conditions in terms of yield. Moreover, a notable reaction is the reaction of the deprotected allylic group with Pd catalyst. An improved overall yield of 11% has been achieved for salvianolic acid N starting from 3,4-dimethoxybenzaldehyde in 11 steps.

An efficient NaOH-promoted synthesis of dihetaryl substituted alkenes from 1,1-dihaloalkenes and 1H-azoles under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated aliphatic, heterocyclic, and aryl substituted 1,1-dihaloalkenes containing functionalities such as nitriles, ethers, and halogens. Imidazoles and triazoles also afforded the desired products.

An efficient copper(ii) catalyzed iodine-promoted synthesis of aroylimidazo[1,2-a][1,3,5]triazines from 2-amino-1,3,5-triazines and chalcones under mild conditions has been developed. The reaction occurred with good yields and excellent regioselectivities, and tolerated chalcone containing functionalities such as ethers, halogens, and nitro groups. The successful application of this methodology for a gram-scale reaction indicates its potential for bulk synthesis.

An efficient copper acetate catalyzed sulfonamidation of arenes via C-H bond activation directed by a 2,4-diamino-1,3,5-triazine chelating group under oxygen as a terminal oxidant has been developed. The reaction shows good regioselectivity and functional group tolerance, as well as providing a straightforward methodology for the preparation of ortho-monosulfonamidated arene derivatives in moderate to high yields. The sulfonamidation at the gram scale can be performed with a good yield.

An efficient ruthenium-catalyzed synthesis of tri-substituted 1,3,5-triazinones from alcohols and guanylureas under mild conditions has been developed. The scope of both the alcohols and guanylureas in the reaction is demonstrated. This ruthenium-catalyzed ring-forming process can be successfully extended to 2-guanidinobenzimidazoles to afford substituted dihydro[1,3,5]triazino[1,2-a]benzimidazoles.

An efficient copper-catalyzed synthesis of 2-arylamino-1,3,5-triazines from 2-aminotriazines with aryl halides under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated aryl iodides containing functionalities such as nitriles, ethers, amides, and halogens. Aryl bromides were also well tolerated.

An efficient ruthenium-catalyzed synthesis of tri-substituted 1,3,5-triazines from alcohols and biguanides under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated benzyl alcohol containing functionalities such as halogens. Monosubstituted to tetrasubstituted biguanidines also afforded the desired products.

An efficient ruthenium-catalyzed synthesis of alkyl-1,3,5-triazies from arylallyl alcohols and biguanides has been developed. The reaction occurred in moderate to good yields and tolerated heterocyclic or aryl allyl alcohols containing functionalities such as alkanes, ethers, and halogens. The reaction proceeds through a one-pot sequence of transfer hydrogenation and condensation steps.

An efficient copper-catalyzed synthesis of substituted 2,4-diamino-1,3,5-triazines from 1,1-dibromoalkenes and biguanides under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated alkyl-, heterocyclic-, or aryl-substituted 1,1-dibromoalkenes containing functionalities such as nitriles, ethers, and halogens. Monosubstituted to tetrasubstituted biguanidines also afforded the desired products.

(E)-2-(6-((E)-2-carboxyvinyl)-2,3-dihydroxyphenyl)-3-(3,4-dihydroxyphenyl) acrylic acid, designated SMND-309, was synthesized starting from 2-hydroxy-3-methoxybenzaldehyde in 12 steps and with an overall yield of 44%. The synthetic key features were the conversion of aryl aldehyde into aryl acetic acid for one-carbon extended, the Perkin condensation, and the Heck coupling for construction of α,β-unsaturated ester.

N-Alkylation of sulfonamides using cyclic ethers as alkylation reagents and Bronsted acid as a catalyst produced pyrrolidine and piperidine derivatives in good yields. When using symmetrical and unsymmetrical ethers as alkylation reagents, mono-N-alkylation of sulfonamides took place to afford the corresponding products.

An efficient copper-catalyzed synthesis of 2-arylamino-1,3,5-triazines from 2-aminotriazines with aryl halides under mild conditions has been developed. The reaction occurred in moderate to good yields and tolerated aryl iodides containing functionalities such as nitriles, ethers, amides, and halogens. Aryl bromides were also well tolerated.

Herein we report that LiAlH4/AlCl3 is a very efficient reagent for the reductive dehydration of aryl propargylic alcohols in tetrahydrofuran solvent at reflux to give 1,3-dienes with good yields and high E selection. The reaction conditions are mild and easy to operate, and a variety of aryl functional groups, such as bromo, fluoro, butyl, and methoxyl groups, are tolerated. With our protocol, useful (E,E)-1,3-dienes can be synthesized. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.

An efficient copper-catalyzed cross-coupling reaction of biguanide hydrochloride derivatives with both aryl iodides and bromides under mild conditions has been developed. The reaction occurred in good yields and tolerated aryl halides containing functionalities such as nitriles, sulfonamides, ethers, and halogens. Alkyl and cyclic substituted biguanidines were also well tolerated.

HgSO4 catalyzed hydrative cyclization of 1,6-heptadiynes is present. This reaction proceeded smoothly under the mild condition for differently 4-sustituted 1,6-diynic substrates giving corresponding 3-methyl-2-cyclohexenones with high to excellent yield. The microwave assisted aldol condensation of cyclohexenones under the catalysis of BiCl3 afforded 3-styryl-cyclohexenones with high regio- and stereo-selectivity.

In the presence of a catalytic amount of Ph 3 PAuNO 3 and H 2 SO 4 ,the hydroalkoxylation of allenes with alcohols has been shown toproceed smoothly and give allylic ethers in good yields and highregio- and stereoselectivity.

A new family of organometallic/inorganic composite Langmuir-Blodgett (LB) films consisting of rigid-rod polyplatinayne polymer ((Pt-T(OMe-Fl)T)? or (Pt-T(F-Fl)T)?, where the triplet bonds are abbreviated by T, and fluorene ring by Fl) as the p-conjugated organometallic molecule, polyoxometalate (POM, POM ¼ K3PMo12O40 ,H 3PW12O40 ,o r H 6P2W18O62) of the Keggin and Dawson structures as the inorganic component, and dimethyldioctadecylammonium bromide (DODA) or a mixture of octadecanoic acid (OA) and docosanoic acid (DA) as the auxiliary film- forming agent were prepared and characterized by p-A isotherms, UV-Vis absorption spectra, photoluminescence spectra, atomic force microscopy imaging, scanning tun- neling microscopy, and low-angle X-ray diffraction. Our experimental results indicate that steady, even, and ordered Langmuir and LB films are formed in pure water and polyoxometalate subphases. It was shown that the POM molecules are probably em- bedded inside the polyplatinayne molecules in the LB film structure and they can quench the luminescence of the Pt polyyne. These Pt-polyyne based LB films display interesting electric conductivity behavior. (Pt-T(OMe-Fl)T)?/DODA/HPW12 monolayer film shows a good electrical conductivity, and the tunneling current amounts to 6100 nA when the voltage is set at 6 8V.V C 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3193-3206, 2008

N-Sulfonylpyrrolidines (III) and (Va,b), piperidine derivative (Vc), and N-alkyl sulfonamides (VII) are synthesized under mild conditions in good yields using a new general and practical one-step protocol.

This paper describes a new method for the highly stereoselective preparation of dithymidine phosphorothioates (TpsT) with the (R) or the (S) configuration at the stereogenic phosphorus atom [(Rp)- or (Sp)-TpsT, respectively], together with the synthesis of oligodeoxyribonucleotides with stereochemically pure phosphate/phosphorothioate mixed backbones through the use of (Rp)- or (Sp)-TpsT as building blocks.Stereochemically pure (Rp)- or (Sp)-TpsT was produced through a five-step process: 1) 1H-tetrazole-promoted thermodynamic equilibration of a diastereomeric mixture of allyl (Rp)- and (Sp)-thymidine 3′,5′-cyclic phosphate to give the (Sp) isomer as the major component, 2) stereospecific sulfurization of the allyl (Sp)-thymidine 3′,5′-cyclic phosphate to afford an allyl (Rp)-thymidine 3′,5′-cyclic phosphorothioate, 3) regioselective and stereoselective methanolysis of the allyl (Rp)-thymidine 3′,5′-cyclic phosphorothioate to provide an allyl methyl (Rp)-thymidine 3′-phosphorothioate as the main product, 4) stereospecific removal of the methyl group from the phosphorothioate moiety to give an allyl (Rp)-5′-O-dimethoxytritylthymidine 3′-phosphorothioate diester, or stereospecific removal of the allyl group from the phosphate moiety to form a methyl (Sp)-5′-O-dimethoxytritylthymidine 3′-phosphorothioate diester, and 5) stereospecific condensation of these (Rp)- and (Sp)-diesters with a 5′-O-free thymidine in a Mitsunobu reaction to produce the allyl (3′–5′)-linked (Sp)-dithymidine phosphorothioate and the methyl (3′–5′)-linked (Rp)-dithymidine phosphorothioate, respectively. The resulting (Rp)- and (Sp)-dithymidine phosphorothioates were converted into their 3′-phosphoramidites. Oligodeoxyribonucleotides with stereochemically pure phosphate/phosphorothioate-mixed backbones were then synthesized by use of these phosphoramidites as building blocks. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)