Enantiospecific Synthesis of All Four Stereoisomers of Novel Bicyclic Arylacetamides as κ-Opioid Agonists

Conformationally constrained bicyclic derivatives of the potent and selective κ-opioid receptor agonist 2-(3,4-dichlorophenyl)-N-methyl-N- [(1S)-1-phenyl-2- (1-pyrrolidinyl)-ethyl] acetam^ide (3, ICI-199, 441) were designed to explore the effect of the conformational restriction and stereochemistry of the pharmacophoric ethylenediamine incorporated into the pyrrolidine on the affinity and κ-selectivity. A facile enantiospecific synthetic route was established to afford all four stereoisomers starting from readily available amino acids through mild cyclization and amide formation.

Monitoring hepatitis C virus treatment rates in an Opioid Treatment Program:A longitudinal study

BACKGROUND Direct-acting antivirals(DAAs)are recommended for the treatment of hepatitis C virus(HCV)infection in patients treated with methadone or buprenorphine.AIM To assess HCV treatment rates in an Opioid Treatment Program(OTP).METHODS This longitudinal study included 501 patients(81.4%men,median age:45 years;interquartile range:39-50 years)enrolled in an OTP between October 2015 and September 2017.Patients were followed until September 2019.Data on sociodemographics,substance use,HCV infection,human immunodeficiency virus(HIV)infection and laboratory parameters were collected at entry.We analyzed medical records to evaluate HCV treatment.Kaplan-Meier methods and Cox regression models were used to analyze the DAA treatment uptake and to identify treatment predictors.RESULTS Prevalence of HCV and HIV infection was 70%and 34%,respectively.Among anti-HCV-positive(n=336)patients,47.2%,41.3%,and 31.9%used alcohol,cannabis,and cocaine,respectively.HCV-RNA tests were positive in 233(69.3%)patients.Twentyeight patients(8.3%)cleared the infection,and 59/308(19.1%)had received interferon-based treatment regimens before 2015.Among 249 patients eligible,111(44.6%)received DAAs.Treatment rates significantly increased over time from 7.8/100 person-years(p-y)(95%CI:5.0-12.3)in 2015 to 18.9/100 p-y(95%CI:11.7-30.3)in 2019.In a multivariate analysis,patients with HIV co-infection were twice as likely to receive DAAs(HR=1.94,95%CI:1.21-3.12)than patients with HCV mono-infection.Current drug use was an independent risk factor for not receiving treatment against infection(HR=0.48,95%CI:0.29-0.80).CONCLUSION HCV treatment is evolving in patients with HCV-HIV co-infection.Ongoing drug use while in an OTP might negatively impact the readiness to treat infection.

Effect of Synthetic Leucopyrokinin Analog [D-AlaS]-[2-8]-Leucopyrokinin （[D-AlaS]-[2-8]-LPK） on Opioid-lnduced Analgesia in Rats

The study was undertaken in order to evaluate effect of synthetic insect neuropeptide leucopyrokinin analog, [D-Ala5]-[2-8]-LPK, on analgesia induced by selective agonists of/a-, 6- and l〈-opioid receptors. The study was performed on male Wistar rats, which a week before the experiments were implanted with polyethylene cannulas into the lateral brain ventricle （icv）. Effect of prior administration of [D-Ala5]-[2-8]-LPK on analgesia induced in rats by next icv administration of equimolar dose of μ-, δ- and -opioid agonists： DAMGO, DPDPE and GR fumarate respectively, was evaluated. Antinociceptive effect was determined in rats by the test of the tail immersion. It was found that two doses of 5 and 10 nmols icv of [D-AlaS]-[2-8]-LPK inhibited analgesia in rats by equimolar doses of DAMGO. This analog also transiently （only in two time intervals） and in one dose of 10 nmols inhibited analgesia induced in rats by icv administration of equimolar DPDPE dose of 10 nmols icv. Obtained results indicate that [D-AlaS]-[2-8]-LPK inhibits antinociceptive effect of DAMGO and in part of DPDPE, i.e. mainly antagonized ~t-opioid receptors. These results correspond with results of our previous study that selective antagonists of μ- and δ-opioid receptors blocked antinociceptive effect of synthetic insect neuropeptide leucopyrokinin and of it active analog [2-8]-leucopyrokinin. We regard that [D-AIaS]-[2-8]-LPK, the first discovered antagonist of leucopyrokinin may be a useful as a probable tool substance in the study of biological effects of insect-derived peptides either in invertebrates or in mammals.