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1.
Phys Chem Chem Phys ; 20(16): 11347-11358, 2018 Apr 25.
Article in English | MEDLINE | ID: mdl-29644372

ABSTRACT

The ability of the carbon nanoring [11]cycloparaphenylene ([11]CPP) for coordinating fullerenes has been tested using a series of hosts, including the pristine fullerenes C60, C70, C76 and C78, the clusterfullerene Sc3N@C80, monometallic endofullerenes Y@C82 and Tm@C82, and dimetallic endofullerenes Y2@C82 and Lu2@C82. A systematic theoretical study employing dispersion corrected density functional methods has been carried out in order to explore the characteristics of the complexes and the strength of the interaction. Depending on the dimer, complexation energies span from around -36 kcal mol-1 with C60 to -53 kcal mol-1 with the C82 derivatives. Dispersion is the main stabilizing contribution in these dimers, so the molecules arrange to maximize the number of close interatomic contacts. Since most fullerenes can properly fill the cavity of the nanoring the stability of the complexes is pretty similar, with the exception of the smallest fullerenes. The complexes with endohedral fullerenes show similar stabilities in all cases studied, with no noticeable dependence on the nature of the endohedral species. The results obtained suggest that fullerenes larger than C76 could be selectively encapsulated by [11]CPP compared to smaller fullerenes.

2.
Phys Chem Chem Phys ; 19(39): 26787-26798, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28948986

ABSTRACT

The complexation of the pristine fullerenes C60 and C70 and the endohedral fullerenes Sc3N@C80 and Sc3N@C68 has been tested using a series of hosts of different nature, including the buckybowls corannulene and sumanene, a zinc porphyrin, a chloro boron subphthalocyanine, and a corannulene pentasubstituted with nitrile groups. A systematic theoretical study has been carried out in order to explore both the strength of the interaction and the feasibility for electron transfer of the dimers. Dispersion is the main stabilizing contribution in these dimers, so both molecules orientate so as to maximize the number of close contacts among atoms. As a consequence, all host molecules interact with C70 by the long axis. C60 and Sc3N@C80 are more spherically shaped, so there is no clear preference for the position of the host molecule, though endohedral fullerenes are encapsulated preferentially by the face without contacts with the inner cluster. Complexation energies increase with the contact surface between molecules in the complex. The most stable complexes with fullerenes are formed by the subphthalocyanine and the CN-pentasubstituted corannulene. Depending on the dimer, complexation energies span from around -15 kcal mol-1 of C60 with corannulene to -24 kcal mol-1 of Sc3N@C80 with the subphthalocyanine. Some of the dimers seem to be capable of acting as a donor-acceptor pair, leading to charge transfer states with a neat separation of charge, thus being candidates for organic photovoltaic devices. Endohedral fullerenes are less prone to these donor-acceptor transitions, with charge transfer taking place from the carbon cage to the endohedral cluster. cora5CN, with its inverted polarity, also shows charge transfer upon excitation but with the fullerene acting as a donor and the buckybowl as an acceptor.

3.
Dalton Trans ; 53(34): 14422-14432, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39140836

ABSTRACT

A sample of NaCr(P2O7) was synthesized using the solid-state reaction method. X-ray diffraction and Rietveld refinement confirmed the formation of a monoclinic structure with the P21/a space group. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis identified the morphology and homogeneity of the chemical composition. The optical absorption spectrum revealed a direct optical band gap of 2.9 eV and an Urbach energy of 0.44 eV. Notably, the absorption spectrum showed an interference dip on the lowest energy band 4T2g(4F), attributed to spin-orbit coupling between states 2Eg(2G) and 4T2g(4F). This phenomenon was analyzed using the Neuhauser model based on coupled potential energy surfaces. From this analysis, the electronic structure of Cr3+ (3d3) ions in the NaCr(P2O7) sample was determined, enabling a reliable calculation of Racah and crystal-field parameters. The results showed good agreement between experimental and theoretical energy levels. The study demonstrates the impact of spin-orbit interactions using the coupled potential energy surface model.

4.
Heliyon ; 10(16): e36188, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39253172

ABSTRACT

The Lithium-chromium phosphate Li3Cr2(PO3)4 sample was synthesized via the solid-state reaction method. The morphological integrity and chemical homogeneity were verified by energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM). Infrared and Raman patterns were also analyzed. Optical absorption spectrum analysis, conducted within the range of 10000 cm-1 to 30000 cm-1 at room temperature, yielded some optical parameters (Eg, Eu, δ , k, n). The Neuhauser model is used to interpret the interference dip which was on the absorption spectrum of Li3Cr2(PO3)4. The Fourier transform of the autocorrelation function leads to the Zero Phonon Lines of the observed absorption energies. The electronic structure of Cr3+ (3d (Huang et al., 2009) 33) ions in Li3Cr2(PO3)4 was calculated using Racah method, which allowed for precise calculations of Racah and crystal-field parameters. The results showed good agreement between the theoretical and experimental energy levels.

5.
Dalton Trans ; 53(18): 7721-7733, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38623734

ABSTRACT

The spinels ZnAl1.99-xHoxCr0.01O4 (with x = 0 and 0.001) were synthesized using a solid-state method, and various techniques were employed for their characterization. X-ray diffraction (XRD) analysis confirmed a cubic spinel structure with the Fd3̄m space group for both spinels. The morphology and homogeneity of the chemical composition were determined using scanning electron microscopy (SEM) and energy dispersive X-ray analysis. Raman and infrared vibrational spectroscopy techniques were also employed for analysis. The optical band gap (Eg) was determined from UV/vis absorption spectra, and the direct transition behavior was confirmed by Tauc's law. The observed large disorder and defect concentration are attributed to the presence of Cr3+ and Ho3+ ions, explaining this behavior. The electron paramagnetic resonance (EPR) measurement presented different types of traps. Room temperature absorption spectra exhibited multiple peaks corresponding to the 3d-3d and 4f-4f transitions of Cr3+ and Ho3+ ions. The results obtained validate the significance of our compounds in optoelectronic device applications.

6.
Heliyon ; 10(8): e29241, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38660272

ABSTRACT

The ZnAl1.999Ho0.001O4 phosphor, prepared by the solid-state method, crystallizes in the cubic spinel structure. Morphology and chemical composition homogeneity were determined via Energy Dispersive X-ray and SEM analysis. The (Eg) optical band gap was evaluated from the UV/vis absorption spectrum, confirming direct transition behavior according to Tauc's law. The Urbach energy (Eu) in the ZnAl1.999Ho0.001O4 spinel was higher than that in the ZnAl2O4 spinel, indicating increased disorder and a higher concentration of defects due to Ho3+ ions. The penetration depth (δ(λ)), optical extinction (k(λ)), and refractive index (n(λ)) were assessed across wavelengths (λ). The room temperature absorption spectrum revealed several peaks corresponding to the 4f-4f transitions of Ho3+ ions.

7.
Article in English | MEDLINE | ID: mdl-38083113

ABSTRACT

Studies show that there is a high prevalence of pelvic floor dysfunctions which negatively affect the quality of life of people who suffer from them. The few sensory mechanisms that pelvic floor muscles have to inform the brain of their situation can make it difficult to perform voluntary contractions or identify risk factors. Currently, there is no consensus to improve this proprioception. This work introduces the development of a novel intravaginal device that is connected to a mobile data acquisition system and able to discern the correct contraction of the pelvic floor muscles versus contraction of adjacent muscles or abdominal thrust efforts. A cross-sectional pilot clinical study has been carried out to validate this end with healthy adult nulliparous woman with good pelvic floor muscles contraction capability in supine position.Clinical relevance- The proposed system allows a personalized and real-time assessment of the contractile capability of the pelvic floor muscles (PFM), distinguishing between muscular plans (deep/superficial PFM), between sides (right/left PFM), and between pressures from the PFM and intra-abdominal muscles (IAP). The development of an intravaginal device which is able to simultaneously measure all these features is an important advancement in this field since it can provide information in real time on the contraction capability of all the PFM as well as on the influence of the IAP during different PFM exercises.


Subject(s)
Pelvic Floor , Quality of Life , Adult , Female , Humans , Cross-Sectional Studies , Muscle Contraction/physiology , Exercise Therapy
8.
Parasitology ; 139(11): 1375-424, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22776427

ABSTRACT

Infections by the protozoan parasite Toxoplasma gondii are widely prevalent in humans and animals in Brazil. The burden of clinical toxoplasmosis in humans is considered to be very high. The high prevalence and encouragement of the Brazilian Government provides a unique opportunity for international groups to study the epidemiology and control of toxoplasmosis in Brazil. Many early papers on toxoplasmosis in Brazil were published in Portuguese and often not available to scientists in English-speaking countries. In the present paper we review prevalence, clinical spectrum, molecular epidemiology, and control of T. gondii in humans and animals in Brazil. This knowledge should be useful to biologists, public health workers, veterinarians, and physicians. Brazil has a very high rate of T. gondii infection in humans. Up to 50% of elementary school children and 50-80% of women of child-bearing age have antibodies to T. gondii. The risks for uninfected women to acquire toxoplasmosis during pregnancy and fetal transmission are high because the environment is highly contaminated with oocysts. The burden of toxoplasmosis in congenitally infected children is also very high. From limited data on screening of infants for T. gondii IgM at birth, 5-23 children are born infected per 10 000 live births in Brazil. Based on an estimate of 1 infected child per 1000 births, 2649 children with congenital toxoplasmosis are likely to be born annually in Brazil. Most of these infected children are likely to develop symptoms or signs of clinical toxoplasmosis. Among the congenitally infected children whose clinical data are described in this review, several died soon after birth, 35% had neurological disease including hydrocephalus, microcephaly and mental retardation, 80% had ocular lesions, and in one report 40% of children had hearing loss. The severity of clinical toxoplasmosis in Brazilian children may be associated with the genetic characteristics of T. gondii isolates prevailing in animals and humans in Brazil.


Subject(s)
Toxoplasmosis/epidemiology , Animals , Brazil/epidemiology , Humans , Prevalence , Risk Factors , Toxoplasma/physiology , Toxoplasmosis/pathology , Toxoplasmosis/prevention & control , Toxoplasmosis/transmission , Toxoplasmosis, Congenital/epidemiology , Toxoplasmosis, Congenital/pathology
9.
Dis Aquat Organ ; 99(2): 145-51, 2012 Jun 13.
Article in English | MEDLINE | ID: mdl-22691983

ABSTRACT

Virulence factors for Aeromonas salmonicida subsp. salmonicida (ASS) strains isolated from cultured turbot Psetta maxima L. are unknown with regard to this host. The presence of virulence genes associated with different stages of ASS infection in salmonids (vapA, tapA, fla, ascV, ascC, aexT, satA and aspA) was analysed using a polymerase chain reaction (PCR) technique in ASS strains isolated from turbot. Other ASS strains isolated from salmonids and environmental A. salmonicida (AS) strains were included for comparison. The presence of the genes was evaluated with respect to ASS virulence in turbot based on intraperitoneal and bath challenges. The genetic profile, including all of the genes studied, that was linked to virulent behaviour after intraperitoneal challenge was significantly more frequent in strains isolated from turbot than in those from salmonids or the environment. The data prove that it is not possible to predict the virulence of ASS in turbot based only on the presence of all genes tested. Moreover, the combined PCR results of vapA, aexT, ascV and ascC were useful for separating most of the ASS from environmental A. salmonicida strains. An association between virulence or genetic profile and the geographical or facility origin of the strains was not found.


Subject(s)
Aeromonas salmonicida/pathogenicity , Fish Diseases/microbiology , Flatfishes/microbiology , Gram-Negative Bacterial Infections/veterinary , Virulence Factors/metabolism , Aeromonas salmonicida/classification , Aeromonas salmonicida/metabolism , Animals , Gene Expression Regulation, Bacterial/physiology , Gram-Negative Bacterial Infections/microbiology , Polymerase Chain Reaction , Virulence
10.
Genes Immun ; 12(7): 589-94, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21633373

ABSTRACT

Mapping murine genes controlling cutaneous leishmaniasis (CL) identified Fli1 as a candidate influencing resistance to L. major and enhanced wound healing. We examine FLI1 as a gene controlling CL and mucosal leishmaniasis (ML) caused by L. braziliensis in humans. Intron 1 single nucleotide polymorphisms tagging promoter and enhancer elements were analysed in 168 nuclear families (250 CL; 87 ML cases) and replicated in 157 families (402 CL; 39 ML cases). Robust case-pseudocontrol logistic regression analysis showed association between allele C (odds ratio (OR) 1.65; 95% confidence interval 1.18-2.29; P=0.003) of FLI1_rs7930515 and CL in the primary sample that was confirmed (OR 1.60; 95% confidence interval 1.10-2.33; P=0.014) in the replication set (combined P=1.8 × 10(-4)). FLI1_rs7930515 is in linkage disequilibrium with the functional GAn microsatellite in the proximal promoter. Haplotype associations extended across the enhancer, which was not polymorphic. ML associated with inverse haplotypes compared with CL. Wound healing is therefore important in CL, providing potential for therapies modulating FLI1.


Subject(s)
Genetic Predisposition to Disease , Leishmaniasis, Cutaneous/genetics , Polymorphism, Single Nucleotide , Proto-Oncogene Protein c-fli-1/genetics , Alleles , Brazil , Gene Frequency , Haplotypes , Humans , Introns , Racial Groups/genetics
11.
Eur J Clin Microbiol Infect Dis ; 28(4): 345-51, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18855029

ABSTRACT

The purpose of this study was to investigate the antibodies to Toxoplasma gondii in human immunodeficiency virus (HIV)-infected pregnant women and to determine the association between serological profile and the risk of congenital toxoplasmosis. The study, conducted in a public maternity ward from May 2002 to April 2005, included all HIV-infected women who delivered live infants during the 36 months, and, as a control group, all HIV-negative women that delivered live infants in the first 12 months of the study. Antibodies to T. gondii were detected in 1,624 of 2,421 HIV-negative women (67%; 95% confidence interval [CI] 65-69%) and in 121 of 168 HIV-infected patients (72%; 95% CI 65-79%). A total of 547 HIV-negative and 103 HIV-infected patients were tested at delivery and had positive T. gondii-specific IgG. In HIV-negative women, the median of the specific IgG concentration was 79 (interquartile range 38-160), and in HIV-infected patients, it was 283 (interquartile range 94-704) (P < 0.001). In the group of co-infected women, the only infant with congenital toxoplasmosis was born to a mother with acute toxoplasmosis infection acquired during pregnancy who did not have a high specific IgG concentration or a positive result for specific IgM. We concluded that high T. gondii-specific IgG values were much more frequent among HIV-infected pregnant women, but it did not translate into an increased risk of maternal-fetal transmission of toxoplasmosis.


Subject(s)
AIDS-Related Opportunistic Infections/immunology , Antibodies, Protozoan/blood , Pregnancy Complications, Parasitic/immunology , Toxoplasma/immunology , Toxoplasmosis, Congenital/epidemiology , Toxoplasmosis/immunology , AIDS-Related Opportunistic Infections/epidemiology , Animals , Cross-Sectional Studies , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Pregnancy , Pregnancy Complications, Parasitic/epidemiology , Risk Factors , Toxoplasmosis/epidemiology , Toxoplasmosis, Congenital/immunology
16.
Br J Pharmacol ; 172(14): 3579-95, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25857324

ABSTRACT

BACKGROUND AND PURPOSE: Sativex(®) is an oromucosal spray, containing equivalent amounts of Δ(9) -tetrahydrocannabinol (Δ(9) -THC) and cannabidiol (CBD)-botanical drug substance (BDS), which has been approved for the treatment of spasticity and pain associated to multiple sclerosis (MS). In this study, we investigated whether Sativex may also serve as a disease-modifying agent in the Theiler's murine encephalomyelitis virus-induced demyelinating disease model of MS. EXPERIMENTAL APPROACH: A Sativex-like combination of phytocannabinoids and each phytocannabinoid alone were administered to mice once they had established MS-like symptoms. Motor activity and the putative targets of these cannabinoids were assessed to evaluate therapeutic efficacy. The accumulation of chondroitin sulfate proteoglycans (CSPGs) and astrogliosis were assessed in the spinal cord and the effect of Sativex on CSPGs production was evaluated in astrocyte cultures. KEY RESULTS: Sativex improved motor activity - reduced CNS infiltrates, microglial activity, axonal damage - and restored myelin morphology. Similarly, we found weaker vascular cell adhesion molecule-1 staining and IL-1ß gene expression but an up-regulation of arginase-1. The astrogliosis and accumulation of CSPGs in the spinal cord in vehicle-infected animals were decreased by Sativex, as was the synthesis and release of CSPGs by astrocytes in culture. We found that CBD-BDS alone alleviated motor deterioration to a similar extent as Sativex, acting through PPARγ receptors whereas Δ(9) -THC-BDS produced weaker effects, acting through CB2 and primarily CB1 receptors. CONCLUSIONS AND IMPLICATIONS: The data support the therapeutic potential of Sativex to slow MS progression and its relevance in CNS repair.


Subject(s)
Cannabidiol/therapeutic use , Disease Models, Animal , Multiple Sclerosis/drug therapy , Multiple Sclerosis/virology , Plant Extracts/therapeutic use , Theilovirus/pathogenicity , Animals , Cannabidiol/administration & dosage , Disease Progression , Dose-Response Relationship, Drug , Dronabinol , Drug Combinations , Drug Therapy, Combination , Mice , Mice, Inbred Strains , Multiple Sclerosis/pathology , Plant Extracts/administration & dosage
17.
Rev Calid Asist ; 30(1): 38-43, 2015.
Article in Spanish | MEDLINE | ID: mdl-25666087

ABSTRACT

Decision making in the patient with chronic advanced disease is especially complex. Health professionals are obliged to prevent avoidable suffering and not to add any more damage to that of the disease itself. The adequacy of the clinical interventions consists of only offering those diagnostic and therapeutic procedures appropriate to the clinical situation of the patient and to perform only those allowed by the patient or representative. In this article, the use of an algorithm is proposed that should serve to help health professionals in this decision making process.


Subject(s)
Algorithms , Chronic Disease/therapy , Clinical Decision-Making , Humans , Terminal Care
18.
Rev Bras Ortop ; 50(1): 94-9, 2015.
Article in English | MEDLINE | ID: mdl-26229884

ABSTRACT

OBJECTIVE: To compare the use of anchors with double and single-thread loading in the single-row Bankart arthroscopic procedure. METHODS: 252 patients (258 shoulders) underwent Bankart arthroscopic surgery with evaluation after a minimum follow-up of 2 years. They underwent repairs either using anchors with single loading of a high-resistance non-absorbable braided thread (206 shoulders; group AS) or using double loading of thread with the same characteristics (52 shoulders; group AD). The patients were evaluated using the UCLA and Carter-Rowe scales. The patients' return to sports activity and recurrences were also compared. RESULTS: There was no significant difference between the groups regarding the surgical failure rate (group AS 5.8%; group AD 7.7%; p = 0.62). Group AS presented a better mean Carter-Rowe score (group AS 94.4; group AD 88.6; p < 0.05) and greater return to the same sports level (group AS 79.1; group AD 72.1; p < 0.05). CONCLUSION: Use of anchors with double thread loading did not show any clinical advantage for arthroscopic repair of traumatic anterior shoulder instability, in relation to use of single-thread anchors, over a 2-year follow-up.


OBJETIVO: Comparar o uso de âncoras com carregamento duplo e com carregamento simples de fio no procedimento artroscópico de Bankart com fileira simples. MÉTODOS: Foram submetidos à cirurgia artroscópica de Bankart e avaliados após seguimento mínimo de dois anos 252 pacientes (258 ombros). Foram submetidos a reparo com âncoras com carregamento simples de fio trançado não absorvível de alta resistência 206 ombros (grupo AS) e com âncoras com carregamento duplo com fios de mesmas características 52 (grupo AD). Os pacientes foram avaliados segundo as escalas UCLA e Carter-Rowe. O retorno à atividade esportiva e a recidiva também foram comparados. RESULTADOS: Não houve diferença significante entre os grupos quanto à taxa de falha cirúrgica (grupo AS 5,8%; grupo AD 7,7%; p = 0,62). O grupo AS apresentou melhor Carter-Rowe médio (grupo AS 94,4; grupo AD 88,6; p < 0,05) e maior retorno ao mesmo nível esportivo (grupo AS 79,1; grupo AD 72,1; p < 0,05). CONCLUSÃO: O uso de âncoras com carregamento duplo de fios não demonstrou vantagem clínica no reparo artroscópico da instabilidade anterior traumática do ombro em relação ao uso de âncoras simples no seguimento de dois anos.

19.
Rev Bras Ortop ; 50(2): 200-5, 2015.
Article in English | MEDLINE | ID: mdl-26229917

ABSTRACT

OBJECTIVE: To compare the functional results from high and low-grade isolated partial lesions of the supraspinatus tendon of bursal and articular types, after arthroscopic treatment. METHODS: Sixty-four patients with isolated partial lesions of the supraspinatus tendon were evaluated. The mean length of follow-up was 76 months (range: 29-193). The mean age was 59 years (range: 36-82). The dominant side was affected in 44 patients (68.8%). There were 35 bursal lesions (54.7%) and 29 articular lesions (45.3%). We used the Ellman classification and characterized the lesions as low or high-grade according to whether they affected less than or more than 50% of the tendon thickness, respectively. Debridement was performed in 15 patients (23.5%), repair without completing the lesion in 11 (17%) and repair after completing the lesion in 38 (59.5%). The functional assessments on the patients were done using the Constant & Murley and UCLA scores. RESULTS: The mean Constant & Murley score among the patients with bursal lesions was 82.64 ± 6.98 (range: 59.3-99) and among those with articular lesions, 83.57 ± 7.58 (range: 66-95), while the mean UCLA score in the bursal lesions was 33.37 ± 2.85 (range: 21-35) and in the articular lesions, 32.83 ± 2.95 (range: 22-35). CONCLUSION: Videoarthroscopic treatment of partial lesions of the rotator cuff presents good or excellent results when the low-grade lesions are debrided and the high-grade lesions are completed and repaired. These results are maintained over the long term, with a high satisfaction rate and few complications.


OBJETIVO: Comparar os resultados funcionais, após o tratamento artroscópico, das lesões parciais isoladas do tendão supra-espinal dos tipos bursal e articular nos graus alto e baixo. MÉTODOS: Foram avaliados 64 pacientes com lesões parciais isoladas do tendão supra-espinal. Seguimento médio de 76 meses (29 a 193). A média de idade foi de 59 anos (36 a 82). O lado dominante foi acometido em 44 pacientes (68,8%). Observadas 35 lesões bursais (54,7%) e 29 articulares (45,3%). Usamos a classificação de Ellman e caracterizamos as lesões como baixo e alto grau quando acometiam menos ou mais de 50% de sua espessura, respectivamente. Foi feito desbridamento em 15 pacientes (23,5%), reparo sem completar a lesão em 11 (17%) e reparo após completar a lesão em 38 (59,5%). A avaliação clínica funcional dos pacientes foi feita com o uso dos escores de Constant & Murley e UCLA. RESULTADOS: A média dos escores de Constant dos pacientes com lesão bursal foi de 82,64 ± 6,98 (59,3 a 99) e com lesão articular foi de 83,57 ± 7,58 (66 a 95), enquanto que a média do UCLA nas lesões bursais foi de 33,37 ± 2,85 (21 a 35) e nas lesões articulares foi de 32,83 ± 2,95 (22 a 35). CONCLUSÃO: O tratamento videoartroscópico das lesões parciais do manguito rotador apresenta resultados bons/excelentes quando as lesões de baixo grau são desbridadas e as lesões de alto grau são completadas e reparadas. Esses resultados se mantêm em longo prazo, com alto índice de satisfação e poucas complicações.

20.
Org Lett ; 3(4): 611-4, 2001 Feb 22.
Article in English | MEDLINE | ID: mdl-11178838

ABSTRACT

[reaction: see text] Chiral nonracemic bicyclic lactam 3, easily accessible by cyclodehydration of (R)-phenylglycinol and racemic methyl 4-formylhexanoate, was converted to the unsaturated lactams 5, which undergo the stereoselective conjugate addition of lower order cyanocuprates to ultimately lead to enantiopure cis-3,4-disubstituted and 3,4,5-trisubstituted piperidines.


Subject(s)
Heterocyclic Compounds, 2-Ring/chemical synthesis , Lactams/chemistry , Piperidines/chemical synthesis , Heterocyclic Compounds, 2-Ring/chemistry , Molecular Structure , Piperidines/chemistry , Stereoisomerism
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