The first copper-catalyzed formal carboboration of alkynes, in which a C-B bond and a C-C bond are created in a single catalytic cycle, is presented. The reaction proceeds with high regioselectivity and syn-stereoselectivity to form tri- and tetrasubstituted vinylboronic esters from commercially available bis(pinacolato)diboron. A subsequent cross-coupling reaction gives access to highly substituted alkenes.

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The aza-Henry reaction of nitroalkanes with the C=N group of 2-aryl-3H-indol-3-ones catalyzed by thiourea-chincona derivatives takes place with good yield and high ee's.

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Background Early antiretroviral therapy (ART) initiation (ie, within 3 months of infection) limits establishment of the HIV reservoir. However, the effect of early ART initiation on the long-term dynamics of the pool of infected cells remains unclear.Methods In this longitudinal analysis, we included cisgender men who have sex with men (MSM) and transgender women (aged 18-54 years) at high risk for HIV infection, enrolled in the ongoing longitudinal MERLIN study in Peru between Oct 28, 2014, and Nov 8, 2018. Participants were eligible if they had been infected with HIV less than 90 days before enrolment, and if they had cryopreserved peripheral blood mononuclear cell (PBMC) samples. Participants were stratified into three groups on the basis of whether they initiated ART at 30 days or less (acute group), at 31-90 days (early group), or more than 24 weeks (deferred group) after the estimated date of detectable infection. PBMC samples were collected before ART initiation and longitudinally for up to 4 years on ART. The main outcomes were to establish the size of the HIV reservoir before ART initiation and to assess the effect of the timing of ART initiation on the decay of the HIV reservoir over 4 years follow-up. We quantified viral load, and isolated CD4 cells to quantify total HIV DNA, integrated HIV DNA and 2-long terminal repeat circles. Longitudinal analysis of active and inducible HIV reservoirs were measured by quantifying the frequency of CD4 cells producing multiply-spliced HIV RNA ex vivo and after in-vitro stimulation with a tat/rev induced limiting dilution assay (TILDA). A mixed-effects model from the time of ART initiation was used to measure longitudinal decays in viral loads and each HIV reservoir measure in each of the three groups.Findings We included 56 participants in this analysis, all of whom were MSM: 15 were in the acute group, 19 were in the early group, and 22 were in the deferred group. Participants in all three groups had similar levels of all HIV reservoir markers before ART initiation. All participants, including those in the acute group, had a pool of transcriptionally silent HIV-infected cells before ART initiation, as indicated by a substantial increase in TILDA measures upon stimulation. Longitudinal analysis over 4 years of ART revealed a biphasic decay of all HIV persistence markers, with a rapid initial decline followed by a slower decay in all participants. During the first-phase decay, the half-lives of both total and integrated HIV DNA and TILDA measures were significantly shorter in the acute group than in the early and deferred groups. During the second-phase decay, HIV reservoir markers continued to decline only in participants in the acute group.Interpretation Participants who initiated ART within 30 days or less of HIV infection showed a steeper and more sustained decay in HIV reservoir measures, suggesting long-term benefit of acute ART initiation on reservoir clearance.

1,3-Dipolar cycloadditions of C,N-cyclic azomethine imines with α,β-unsaturated aldehydes can be performed with complete control of the regio-, exo-, and enantioselectivity under aminocatalytic conditions. The so far never studied competence of the iminium-dienamine reactivity inherent to β-alkyl α,β-unsaturated aldehydes was studied, which was possible by allowing achievement of complete control of the chemoselectivity in reactions of the β-arylmethyl derivatives with azomethine imines by using different additives and organocatalysts, whose role has been rationalized by DFT calculations and chemical proofs. Thus, it has been possible to selectively obtain the pyrazolidines resulting from both the attack to the C2-C3 (via iminium) and the C3-C4 (via dienamine) bonds at the starting enals, which can be used as precursors of interesting tetrahydroisoquinolinic compounds.

Background In addition to demonstrated public health benefits on reducing transmission, it remains unclear how early antiretroviral therapy (ART) must be started after acquisition of human immunodeficiency virus (HIV) to maximize individual benefits. Methods We conducted an open-label randomized clinical study in Lima, Peru among adult men who have sex with men and transgender women with acute (HIV-antibody negative/HIV-1 RNA positive) or recent (confirmed negative HIV-antibody or RNA test within 3 months) HIV infection, who were randomized to start ART immediately versus defer by 24 weeks. We evaluated outcomes by treatment arm and immunologic markers by days since estimated date of detectible infection (EDDI). Results Of 216 participants, 105 were assigned to immediate arm and 111 to deferred arm (median age 26.8 years, 37% with acute HIV). The incidence of non-ART-related adverse events was lower in immediate versus deferred arm (83 vs 123/100 person-years, IRR 0.67 (95% confidence interval [CI] .47, .95; P = .02), the difference dominated by fewer infections in those treated immediately. After 24 weeks of ART, between-group differences in CD4/CD8 cell ratio lessened (P = .09 overall), but differences between those initiating ART ≤ 30 days from EDDI (median 1.03, interquartile range [IQR] 0.84, 1.37), and those initiating > 90 days (0.88, IQR 0.61, 1.11) remained, P = .02. Principal components analysis of 20 immune biomarkers demonstrated distinct patterns between those starting ART > 90 days from EDDI versus those starting within 30 or 90 days (both P < .001). Conclusions To our knowledge, this is the only evaluation of randomized ART initiation during primary HIV and provides evidence to explicitly consider acute HIV in World Health Organization recommendations for universal ART. Clinical Trials Registration NCT01815580.

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