A NEW SYNTHETIC ROUTE TO α-DAMASOONE

A new synthetic route to α—damascone (4) starting from citral is described-The synthesis features allylatioa of α—cyclocitral (1) with allylic bromide in the presence of tin powder to give the crucial intermediate 1—(2',6',6'—trimethylcyclo— hexen —2'—yl)—3—buten —1—ol(2a) and (2b) in a combined yield of 70%.

A New Synthetic Route to Di-η~5-Cyclopentadienyl Ytterbium(Ⅱ)Tetrafuranate (η~5-C_5H_5)_2Yb(THF)_2 and Its Crystal Structure

In recent years,the organometallic ehemistry of the lanthanide metals in low oxidation states has beenactively investigated.The synthesis of the low一valent lanthanide eomPlexes has the signifieant meanings ontheory and praeti

NEW SYNTHETIC METHOD OF 4,4'-OXYBIS(BENZOIC ACID)AND ITS APPLICATION IN POLYESTER

4,4'-Oxybis(benzoic acid)(Ⅰ)is an important monomer for making synthetic resin,heat resistant film and liquid crystal fiber,etc.It has been synthesized either by the oxidation of 4,4'-dimethyl diphenyl ether,or by the electrophilic substitution of diphenyl ether,these substituents introduced into the benzene ring can be further transformed into carboxylic groups.Diphenyl ethers are usually prepared from phenols and halobenzenes through Ullmann resction.Due to the high reaction temerature(usually above 200℃),long time heating and the formation of isomers,it is difficult to obtain pure products in high yields.

A NEW SYNTHETIC APPROACH TO PHOSPHONOPEPTIDE WITH PHOSPHONAMIDE MOIETY

A novel tricomponental condensation leading to p-nitrophenyl- ethyl hydrogen substituted benzylphosphonates was described.The use of these compounds for the synthesis of phosphonopeptide with phosphonamide moiety was demonstrated.

INVESTIGATION ON THE NEW SYNTHETIC REACTIONS AND MECHANISMS OF SUBSTITUTED DIPHENYL ETHEPS

In the presence of alkali nitrite and carbonate,some nitrobenzenes subs- tituted by strongly electron withdrawing group undergo a self condensation in an aprotic polar sotvent to give symmetrical disubstituted diphenyl ethers in good yields.A possible mechanism is discussed,the nucteophilic aromatic substitution S_NAr and S_(Ru)Ar may occur simultaneously.

HIV infection among new synthetic drug abusers： a pilot study in Beijing

Background Following the increased human immunodeficiency virus （HIV） notification （infection） rates via sexual transmission and increased abuse of new synthetic drugs instead of heroin in China, a study on HIV infections and risk factors among synthetic drugs and heroin users in Beijing was conducted to provide a cue for further development of targets and strategies of HIV/AIDS control and prevention for different drug populations. Methods A total of 428 subjects including 224 heroin users and 204 new synthetic drug users was recruited from communities in Beijing by convenience sampling. A X2 test was used to compare HIV and syphilis infections between the two subpopulations. Logistic regression models were used to evaluate factors related to HIV, syphilis infections and abuse of synthetic drugs. Results Unbalanced distributions of demographics were detected between the two subpopulations. Compared with heroin users, most users of synthetic drugs were migrants, single and of younger age （age 〈30 years）. Ten HIV infections and twenty-four syphilis infections were confirmed among 428 subjects. No significant difference in HIV infection was found between the two subpopulations （crude odds ratio （OR） =0.46, 95% confidence interval （CI）： 0.07-15.80 and adjusted odds ratio （AOR） =1.26, 95% Ch 0.09-18.28） while four times as many syphilis infections were identified among users of synthetics drugs （AOR=3.92, 95% CI： 1.06-14.56）. HIV and syphilis infections appeared to work synergistically.The migrants who were of Han ethnicity, single and who had stayed in Beijing for more than six months were more likely to abuse synthetics drugs. Conclusions The new synthetic drug users and heroin users are different subpopulations. We optimistically speculate that HIV has not yet been introduced into the former in Beijing, but considering higher syphilis infections in synthetic drug users and the role of syphilis in HIV infection, synthetic drug users, as a possible and important driver of the HIV/AIDS epidemic in Beijing, should be paid more attention in HIV prevention and control strategies.

Production of synthetic hydrocarbons from coal through its underground gasification

The problem of the high-level processing of coal into synthetic motor fuels assumes worldwide actual meaning nowadays. Thereat, it is important especially for countries and regions which possess extensive coal resources and are forced to be guided by the import of liquid and gas hydrocarbons. However, a greater emphasis is paid to the given issue in Russia-The development of the federal program for highlevel processing of coal into synthetic motor fuels was initiated. This article describes options of underground coal gasification (UCG) use for the generation of hydrocarbons from UCG gas in the process of the Fischer-Tropsch synthesis (FTS). The technical and economic analysis of the integrated UCG-FTS powerchemical factories has detected their investment attractiveness and practicability of experimental-industrial testing at coal deposits of the Russian Federation.

Novel synthetic opioids-toxicological aspects and analysis

Over the past few years,there has been an emerging number of new psychoactive drugs.These drugs are frequently mentioned as“legal highs”,“herbal highs”,“bath salts”and“research chemicals”.They are mostly sold and advertised on online forums and on the dark web.The emerging new psychoactive substances are designed to mimic the effects of psychoactive groups,which are often abused drugs.Novel synthetic opioids are a new trend in this context and represent an alarming threat to public health.Given the wide number of fatalities related to these compounds reported within the last few years,it is an important task to accurately identify these compounds in biologic matrices in order to administer an effective treatment and reverse the respiratory depression caused by opioid related substances.Clinicians dealing with fentanyl intoxication cases should consider that it could,in fact,be a fentanyl analogue.For this reason,it is a helpful recommendation to include synthetic opioids in the routine toxicological screening procedures,including analysis in alternative matrices,if available,to investigate poly-drug use and possible tolerance to opioids.To address this public health problem,better international collaboration,effective legislation,effective investigation,control of suspicious“research chemicals”online forums and continuous community alertness are required.This article aims to review diverse reported fatalities associated with new synthetic opioids describing them in terms of pharmacology,metabolism,posology,available forms,as well as their toxic effects,highlighting the sample procedures and analytical techniques available for their detection and quantification in biological matrices.

Synthesis of novel isoxazolyl bis-thiazolo[3,2-a]pyrimidines

A new synthetic strategy for the synthesis of novel 3-（3-（3-methyl-4-nitroisoxazol-5-yl）-2-phenyl-1-（5,7-diaryl-7H-thia- zolo[3,2-a]pyrimidin-3-yl）propyl）-5,7-diaryl-7H-thiazolo[3,2-a]pyrimidines （7a-i） analogues is described. Reaction of 3-（2- （3-methyl-4-nitroisoxazole-5-yl）-l-phenylethyl）pentane-2,4-dione （3） with two moles of thiourea in presence of iodine and CuO afforded 4-（1-（2-aminothiazol-4-yl）-3-（3-methyl-4-nitroisoxazol-5-yl）-2-aryl propylthiazol-2-amine （5）. Compound 5 on reaction with two moles of chalcone （6） furnished novel 3-（3-（3-methyl-4-nitroisoxazol-5-yl）-2-phenyl-1-（5,7-diaryl-7H-thiazolo[3,2- a]pyrimidin-3-yl）propyl）-5,7-diaryl-7H-thiazolo[3,2-a ]pyrimidines （Ta-i）.