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1.
Article in English | MEDLINE | ID: mdl-38646606

ABSTRACT

Purpose: To assess patient characteristics of users and new initiators of triple therapy for chronic obstructive pulmonary disease (COPD) in Germany. Patients and Methods: Retrospective cohort study of patients with COPD and ≥1 prescription for single-inhaler triple therapy (SITT; fluticasone furoate/umeclidinium/vilanterol [FF/UMEC/VI] or beclomethasone dipropionate/glycopyrronium bromide/formoterol [BDP/GLY/FOR]) or multiple-inhaler triple therapy (MITT), using data from the AOK PLUS German sickness fund (1 January 2015-31 December 2019). The index date was the first date of prescription for FF/UMEC/VI or BDP/GLY/FOR (SITT users), or the first date of overlap of inhaled corticosteroid, long-acting ß2-agonist, and long-acting muscarinic antagonist (MITT users). Two cohorts were defined: the prevalent cohort included all identified triple therapy users; the incident cohort included patients newly initiating triple therapy for the first time (no prior use of MITT or SITT in the last 2 years). Patient characteristics and treatment patterns were assessed on the index date and during the 24-month pre-index period. Results: In total, 18,630 patients were identified as prevalent triple therapy users (MITT: 17,945; FF/UMEC/VI: 700; BDP/GLY/FOR: 908; non-mutually exclusive) and 2932 patients were identified as incident triple therapy initiators (MITT: 2246; FF/UMEC/VI: 311; BDP/GLY/FOR: 395; non-mutually exclusive). For both the prevalent and incident cohorts, more than two-thirds of patients experienced ≥1 moderate/severe exacerbation in the preceding 24 months; in both cohorts more BDP/GLY/FOR users experienced ≥1 moderate/severe exacerbation, compared with FF/UMEC/VI and MITT users. Overall, 97.9% of prevalent triple therapy users and 86.4% of incident triple therapy initiators received maintenance treatment in the 24-month pre-index period. Conclusion: In a real-world setting in Germany, triple therapy was most frequently used after maintenance therapy in patients with recent exacerbations, in line with current treatment recommendations.


Triple therapy (a combination of three different respiratory inhaled medications) is recommended for patients with chronic obstructive pulmonary disease (COPD) who experience repeated short-term symptom flare-ups when taking dual therapy (a combination of two different respiratory medications). Previously, patients had to take triple therapy using two or three separate inhalers. More recently, single-inhaler triple therapies have been developed, meaning patients can take all three different medications at the same time via one single inhaler. This study assessed the characteristics of patients who were already receiving triple therapy, or who started triple therapy (either via multiple inhalers or a single inhaler), in Germany between January 2015 and December 2019. In total, 18,630 patients who were already receiving triple therapy during the study period, and 2932 patients who newly started using triple therapy were included. The study reported that more than two-thirds of included patients had experienced at least one flare-up of COPD symptoms in the 2 years before starting triple therapy. Most patients had also received another therapy for COPD before starting triple therapy. A small proportion of patients started taking triple therapy after receiving no other therapy for COPD in the previous 2 years. The results of the study suggest that triple therapy for COPD in Germany is most often used in accordance with recommendations (patients already receiving therapy and experiencing repeated symptom flare-ups).


Subject(s)
Adrenergic beta-2 Receptor Agonists , Bronchodilator Agents , Drug Combinations , Glycopyrrolate , Muscarinic Antagonists , Nebulizers and Vaporizers , Pulmonary Disease, Chronic Obstructive , Humans , Male , Pulmonary Disease, Chronic Obstructive/drug therapy , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Female , Retrospective Studies , Germany , Aged , Administration, Inhalation , Middle Aged , Muscarinic Antagonists/administration & dosage , Muscarinic Antagonists/adverse effects , Bronchodilator Agents/administration & dosage , Bronchodilator Agents/adverse effects , Adrenergic beta-2 Receptor Agonists/administration & dosage , Adrenergic beta-2 Receptor Agonists/adverse effects , Glycopyrrolate/administration & dosage , Glycopyrrolate/adverse effects , Chlorobenzenes/administration & dosage , Chlorobenzenes/adverse effects , Quinuclidines/administration & dosage , Quinuclidines/adverse effects , Treatment Outcome , Benzyl Alcohols/administration & dosage , Benzyl Alcohols/adverse effects , Beclomethasone/administration & dosage , Beclomethasone/adverse effects , Formoterol Fumarate/administration & dosage , Drug Therapy, Combination , Time Factors , Aged, 80 and over
2.
J Burn Care Res ; 44(6): 1400-1404, 2023 11 02.
Article in English | MEDLINE | ID: mdl-37099804

ABSTRACT

There has been conflicting data on the relationship between burn severity and psychological outcomes. The present study aims to characterize the baseline psychosocial disposition of adults attending outpatient burn clinic at a large urban safety net hospital, as well as the impact of clinical course on self-reported psychosocial well-being. Adult patients attending outpatient burn clinic completed survey questions from the National Institutes of Health Patient-Reported Outcomes Measurement Information System Managing Chronic Conditions: Self-Efficacy for Managing Social Interactions (SEMSI-4) and Managing Emotions (SEME). Sociodemographic variables were collected from surveys and retrospective chart review. Clinical variables included total body surface area burned, initial hospital length of stay, surgical history, and days since injury. Poverty level was estimated by U.S. census data using patient's home ZIP code. Scores on SEME-4 and SEMSI-4 were compared to the population mean by one-sample T-test, and independent variables evaluated for associations with managing emotions and social interactions by Tobit regression while adjusting for demographic variables. The 71 burn patients surveyed had lower scores in SEMSI-4 (mean = 48.0, P = .041) but not SEME-4 (mean = 50.9, P = .394) versus the general population. Marital status and neighborhood poverty level were associated with SEMSI-4, while length of stay and % total body surface area burned were associated with SEME-4. Patients who are single or from poorer neighborhoods may have difficulty interacting with their environment after burn injury and need extra social support. Prolonged hospitalization and increased severity of burn injury may have more impact on emotional regulation; these patients may benefit from psychotherapy during recovery.


Subject(s)
Burns , Social Interaction , Adult , Humans , Retrospective Studies , Burns/epidemiology , Emotions , Risk Factors , Length of Stay
3.
Mult Scler Relat Disord ; 72: 104583, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36905817

ABSTRACT

BACKGROUND: Research suggests that serious infections (SIs), comorbidities, and advanced disability represent key drivers of early death in people with Multiple Sclerosis (pwMS). Nevertheless, further research is warranted to better characterize and quantify the risk of SI among pwMS compared to the general population. METHODS: Our study consisted of a retrospective analysis of claims data provided by a German statutory health insurance fund, AOK PLUS, covering 3.4 million individuals in Saxony and Thuringia from 01/01/2015-31/12/2019. A propensity score (PS) matching method was used to compare the incidence of SIs among people with and without MS. PwMS were required to have ≥1 inpatient or ≥2 confirmed outpatient diagnoses of MS (ICD-10 G35) from a neurologist from 01/01/2016-31/12/2018, while people from the general population could not have any inpatient/outpatient codes for MS during the entire study period. The index date was defined as the first observed MS diagnosis or, in the case of the non-MS cohort, a randomly assigned date within the inclusion period. For both cohorts a PS was assigned, corresponding with their probabilistic likelihood of having MS based on observable factors including patient characteristics, comorbidities, medication use and other variables. People with and without MS were matched using a 1:1 nearest neighbor strategy. An exhaustive list of ICD-10 codes was created in association with 11 main SI categories. SIs were those recorded as the main diagnosis during an inpatient stay. ICD-10 codes from the 11 main categories were sorted into smaller classification units, used to distinguish between infections. A 60-day threshold for measuring new cases was defined to account for the potential risk of re-infection. Patients were observed until the end of the study period (31/12/2019) or death. Cumulative incidence, incidence rates (IRs) and IR ratios (IRRs) were reported during follow-up and at 1-, 2- and 3-years post-index. RESULTS: A total of 4250 and 2,098,626 patients were included in the unmatched cohorts of people with and without MS. Ultimately, one match was identified for all 4,250 pwMS, corresponding with a final population of 8,500 patients. On average, patients were 52.0/52.2 years in the matched MS/non-MS cohorts; the gender breakdown was 72% female. Overall, IRs of SIs per 100 patient years (PY) were higher in pwMS than in those without MS (1 year: 7.6 vs. 4.3; 2 years: 7.1 vs. 3.8; 3 years: 6.9 vs. 3.9). During follow-up, the most common infection types in pwMS were of a bacterial/parasitic origin (2.3 per 100 PY), followed by respiratory (2.0) and genitourinary (1.9) infections. Respiratory infections were most common in patients without MS (1.5 per 100 PY). Differences in the IRs of SIs were statistically significant (p<0.01) at each measurement window, with IRRs ranging from 1.7-1.9. PwMS had a higher risk of hospitalized genitourinary infections (IRR: 3.3-3.8) and bacterial/parasitic infections (2.0-2.3). CONCLUSIONS: The incidence of SIs is much higher in pwMS, than comparators from the general population in Germany. Differences in hospitalized infection rates were largely driven by higher levels of bacterial/parasitic and genitourinary infections in the MS population.


Subject(s)
Multiple Sclerosis , Female , Humans , Male , Comorbidity , Data Analysis , Germany/epidemiology , Multiple Sclerosis/epidemiology , Multiple Sclerosis/drug therapy , Retrospective Studies
4.
Mult Scler Relat Disord ; 68: 104245, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36306609

ABSTRACT

BACKGROUND: People with multiple sclerosis (pwMS) have a higher risk of serious infection (i.e., infection-related hospitalizations) than people without MS. Few studies have explored the risk of serious infections by MS phenotype in a real-world setting. This retrospective study compared the incidence of serious infections among people with relapse remitting MS (RRMS), primary progressive MS (PPMS), and secondary progressive MS (SPMS). METHODS: Adult pwMS were selected from a German claims database, based on one inpatient or two outpatient diagnoses of MS (ICD-10 G35) by a neurologist from 01/01/2016 to 12/31/2018. Three cohorts (RRMS, PPMS, SPMS) were identified based on codes for MS subtypes included in the German Modification of the ICD-10 system. A fourth cohort of unspecified MS patients combined those with conflicting MS subtype diagnoses and multiple unspecified codes for MS. Serious infections were defined as hospitalizations for which infections were selected as the primary inpatient diagnosis. Infections were identified from a basket of ICD-10 codes distributed across 11 main categories, according to possible pathogen (e.g., other bacterial diseases [A30-A49]) or anatomical location (e.g., urinary tract infection [N39.0]). Multiple infections were counted if an interval of at least 60 days was recorded between episodes. Serious infections were counted from index (i.e., first recorded MS code) until the end of the study period or death. Incidence rates (IRs) were reported per 100 patient years (PY). RESULTS: A total of 4,250 pwMS (RRMS: 2,307, PPMS: 282, SPMS: 558, unspecified MS: 1,135) were included; 32 patients progressed from RRMS to SPMS during the follow-up period. Mean (SD) age at baseline was 46.6 (13.6), 61.9 (12.4), and 62.5 (11.8) years in patients with RRMS, PPMS, and SPMS, respectively. Most pwMS were female (RRMS 74.8%, PPMS 62.1%, SPMS 67.4%). Progressive pwMS were more likely to have at least 1 comorbidity (PPMS 87.2%, SPMS 87.5%) compared to those with relapsing MS (61.9%). Most RRMS patients received disease-modifying therapy during follow-up (82.1%), while less than half of progressive MS patients did (PPMS 23.8%, SPMS 31.4%). Over a mean (SD) follow-up period of 3.5 (0.8) years, the IR of serious infections per 100 PY was higher in progressive MS cohorts (PPMS 13.5 [11.3-16.1], SPMS 13.6 [12.0-15.3]) than in the RRMS group (3.4 [3.0-3.7]). Yearly IRs remained stable over time in each cohort. Where anatomical location was specified, respiratory (2.0 per 100 PY) and genitourinary (1.9 per 100 PY) infections were most common. Across all subtypes, higher rates of serious infections were observed in men and older patients. CONCLUSION: Progressive MS, older age and male sex are associated with an increased risk of serious infections. Overall, respiratory and genitourinary infections were the most commonly reported serious infections.


Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Male , Female , Humans , Multiple Sclerosis/epidemiology , Retrospective Studies , Multiple Sclerosis, Chronic Progressive/epidemiology , Comorbidity , Phenotype , Multiple Sclerosis, Relapsing-Remitting/epidemiology
5.
Front Behav Neurosci ; 16: 903980, 2022.
Article in English | MEDLINE | ID: mdl-35990729

ABSTRACT

Introduction: Traumatic brain injury (TBI) is a leading cause of disability in the US. Angiotensin 1-7 (Ang-1-7), an endogenous peptide, acts at the G protein coupled MAS1 receptors (MASR) to inhibit inflammatory mediators and decrease reactive oxygen species within the CNS. Few studies have identified whether Ang-(1-7) decreases cognitive impairment following closed TBI. This study examined the therapeutic effect of Ang-(1-7) on secondary injury observed in a murine model of mild TBI (mTBI) in a closed skull, single injury model. Materials and methods: Male mice (n = 108) underwent a closed skull, controlled cortical impact injury. Two hours after injury, mice were administered either Ang-(1-7) (n = 12) or vehicle (n = 12), continuing through day 5 post-TBI, and tested for cognitive impairment on days 1-5 and 18. pTau, Tau, GFAP, and serum cytokines were measured at multiple time points. Animals were observed daily for cognition and motor coordination via novel object recognition. Brain sections were stained and evaluated for neuronal injury. Results: Administration of Ang-(1-7) daily for 5 days post-mTBI significantly increased cognitive function as compared to saline control-treated animals. Cortical and hippocampal structures showed less damage in the presence of Ang-(1-7), while Ang-(1-7) administration significantly changed the expression of pTau and GFAP in cortical and hippocampal regions as compared to control. Discussion: These are among the first studies to demonstrate that sustained administration of Ang-(1-7) following a closed-skull, single impact mTBI significantly improves neurologic outcomes, potentially offering a novel therapeutic modality for the prevention of long-term CNS impairment following such injuries.

6.
Food Nutr Bull ; 43(1): 3-13, 2022 03.
Article in English | MEDLINE | ID: mdl-34601956

ABSTRACT

Household decision-making influences choices related to the production, sale, purchase, and consumption of nutrient-rich foods. The present study assessed the effect of household decision-making in 2 regions of Ethiopia within 2 groups of households, most vulnerable households and model farmer households. The study focused on identifying barriers and facilitators relating to decisions about nutrient-rich foods-in this case fruits, vegetables, and animal source foods. The results provide insights into how future agricultural programs can affect key aspects of decision-making to maximize the positive impacts on diet and food security.


Subject(s)
Family Characteristics , Rural Population , Animals , Diet , Food Supply , Humans , Nutrients , Vegetables
7.
Neurol Ther ; 11(1): 247-263, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34940956

ABSTRACT

INTRODUCTION: Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease of the central nervous system which causes recurrent relapses, resulting in blindness, paralysis, and spinal cord damage. This study sought to explore the real-world burden, treatment, and cost of NMOSD in Germany using claims data. METHODS: Our study consisted of a retrospective analysis of two anonymized health insurance datasets covering around 9 million patients in Germany from 01/01/2013 to 31/12/2019. NMOSD patients were identified using inpatient and outpatient International Classification of Diseases, Tenth Revision (ICD-10) diagnoses of neuromyelitis optica (NMO; G36.0) and relevant symptom codes. Active periods of disease were identified based on relapse events (including hospitalizations and acute treatment); healthcare resource utilization (HCRU) and direct costs were allocated to active and inactive periods based on treatment dates. Propensity score matching was used to compare HCRU and cost outcomes among patients with and without NMOSD. RESULTS: Overall, 130 patients were identified as having NMOSD (mean age: 46.84 years; 58% female). NMOSD patients recorded 16.52 active and 348.48 inactive days per patient year (PPY). HCRU and associated costs were approximately tenfold higher during active periods than during inactive periods, with the largest share of the cost difference driven by hospitalizations (€6424.09/€259.10 per active/inactive month) and outpatient drug prescriptions (€412.83/€271.58). Direct healthcare costs incurred by patients with NMOSD (€12,913.28 PPY) were approximately threefold higher than those incurred by patients without NMOSD (€4667.66 PPY). Costs of hospitalization (€6448.32/€1937.64 PPY) and outpatient prescriptions (€3335.67/€1037.64 PPY) contributed most strongly to the difference. CONCLUSION: Patients with NMOSD consume substantial healthcare resources and incur heavy costs during active disease phases. This study captured direct measurable healthcare costs and likely underestimates the real societal/emotional burden on patients and their families. Nevertheless, prevention of acute relapses represents one compelling strategy to minimize the economic burden of NMOSD in Germany.

8.
Org Lett ; 22(21): 8430-8435, 2020 11 06.
Article in English | MEDLINE | ID: mdl-33085486

ABSTRACT

We report an alternative approach to the unnatural nucleobase fragment seen in remdesivir (Veklury). Remdesivir displays broad-spectrum antiviral activity and is currently being evaluated in Phase III clinical trials to treat patients with COVID-19. Our route relies on the formation of a cyanoamidine intermediate, which undergoes Lewis acid-mediated cyclization to yield the desired nucleobase. The approach is strategically distinct from prior routes and could further enable the synthesis of remdesivir and other small-molecule therapeutics.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Amidines/chemistry , Antiviral Agents/chemistry , Antiviral Agents/chemical synthesis , Adenosine Monophosphate/chemical synthesis , Adenosine Monophosphate/chemistry , Adenosine Monophosphate/therapeutic use , Alanine/chemical synthesis , Alanine/chemistry , Alanine/therapeutic use , Antiviral Agents/therapeutic use , COVID-19 , Chemistry Techniques, Synthetic , Coronavirus Infections/drug therapy , Cyclization , Pandemics , Pneumonia, Viral/drug therapy
9.
FEMS Microbiol Lett ; 367(20)2020 11 05.
Article in English | MEDLINE | ID: mdl-33045036

ABSTRACT

In Escherichia coli, DNA cytosine methyltransferase (Dcm) methylates the second cytosine in the sequence 5'CCWGG3' generating 5-methylcytosine. Dcm is not associated with a cognate restriction enzyme, suggesting Dcm impacts facets of bacterial physiology outside of restriction-modification systems. Other than gene expression changes, there are few phenotypes that have been identified in strains with natural or engineered Dcm loss, and thus Dcm function has remained an enigma. Herein, we demonstrate that Dcm does not impact bacterial growth under optimal and selected stress conditions. However, Dcm does impact viability in long-term stationary phase competition experiments. Dcm+ cells outcompete cells lacking dcm under different conditions. Dcm knockout cells have more RpoS-dependent HPII catalase activity than wild-type cells. Thus, the impact of Dcm on stationary phase may involve changes in RpoS activity. Overall, our data reveal a new role for Dcm during long-term stationary phase.


Subject(s)
DNA (Cytosine-5-)-Methyltransferases/metabolism , Escherichia coli Proteins/metabolism , Escherichia coli/enzymology , Escherichia coli/growth & development , Microbial Viability/genetics , DNA (Cytosine-5-)-Methyltransferases/genetics , Escherichia coli/genetics , Escherichia coli Proteins/genetics , Gene Knockout Techniques
10.
ACS Cent Sci ; 6(7): 1017-1030, 2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32719821

ABSTRACT

The SARS-CoV-2 pandemic has prompted scientists from many disciplines to work collaboratively toward an effective response. As academic synthetic chemists, we examine how best to contribute to this ongoing effort.

11.
ACS Chem Biol ; 15(6): 1671-1684, 2020 06 19.
Article in English | MEDLINE | ID: mdl-32352753

ABSTRACT

We report the discovery of a novel class of compounds that function as dual inhibitors of the enzymes neutral sphingomyelinase-2 (nSMase2) and acetylcholinesterase (AChE). Inhibition of these enzymes provides a unique strategy to suppress the propagation of tau pathology in the treatment of Alzheimer's disease (AD). We describe the key SAR elements that affect relative nSMase2 and/or AChE inhibitor effects and potency, in addition to the identification of two analogs that suppress the release of tau-bearing exosomes in vitro and in vivo. Identification of these novel dual nSMase2/AChE inhibitors represents a new therapeutic approach to AD and has the potential to lead to the development of truly disease-modifying therapeutics.


Subject(s)
Acetylcholinesterase/drug effects , Alzheimer Disease/drug therapy , Cholinesterase Inhibitors/pharmacology , Enzyme Inhibitors/pharmacology , Sphingomyelin Phosphodiesterase/antagonists & inhibitors , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/therapeutic use , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/therapeutic use , Humans , Structure-Activity Relationship
12.
Org Lett ; 22(11): 4500-4504, 2020 06 05.
Article in English | MEDLINE | ID: mdl-32437158

ABSTRACT

Transient strained cyclic intermediates have become valuable intermediates in modern synthetic chemistry. Although silyl triflate precursors to strained intermediates are most often employed, the instability of some silyl triflates warrants the development of alternative precursors. We report the syntheses of silyl tosylate precursors to cyclohexyne, 1,2-cyclohexadiene, and 1,2-cycloheptadiene. The resultant strained intermediates undergo trapping in situ to give cycloaddition products. Additionally, the results of competition experiments between silyl triflates and silyl tosylates are reported.


Subject(s)
Cycloheptanes/chemical synthesis , Cyclohexenes/chemical synthesis , Silanes/chemistry , Tosyl Compounds/chemistry , Cycloaddition Reaction , Cycloheptanes/chemistry , Cyclohexenes/chemistry , Molecular Structure , Stereoisomerism
13.
Org Lett ; 22(7): 2833-2837, 2020 04 03.
Article in English | MEDLINE | ID: mdl-32208664

ABSTRACT

We report the conversion of amides to carboxylic acids using nonprecious metal catalysis. The methodology strategically employs a nickel-catalyzed esterification using 2-(trimethylsilyl)ethanol, followed by a fluoride-mediated deprotection in a single-pot operation. This approach circumvents catalyst poisoning observed in attempts to directly hydrolyze amides using nickel catalysis. The selectivity and mildness of this transformation are shown through competition experiments and the net-hydrolysis of a complex valine-derived substrate. This strategy addresses a limitation in the field with regard to functional groups accessible from amides using transition metal-catalyzed C-N bond activation and should prove useful in synthetic applications.


Subject(s)
Amides/chemistry , Carboxylic Acids/chemical synthesis , Nickel/chemistry , Carboxylic Acids/chemistry , Catalysis , Hydrolysis , Molecular Structure
14.
Angew Chem Int Ed Engl ; 58(17): 5653-5657, 2019 04 16.
Article in English | MEDLINE | ID: mdl-30811080

ABSTRACT

The chemistry of strained cyclic alkynes has undergone a renaissance over the past two decades. However, a related species, strained cyclic allenes, especially heterocyclic derivatives, have only recently resurfaced and represent another class of valuable intermediates. We report a mild and facile means to generate the parent 3,4-oxacyclic allene from a readily accessible silyl triflate precursor, and then trap it in (4+2), (3+2), and (2+2) reactions to provide a variety of cycloadducts. In addition, we describe a catalytic, decarboxylative asymmetric allylic alkylation performed on an α-silylated substrate, to ultimately permit access to an enantioenriched allene. Generation and trapping of the enantioenriched cyclic allene occurs with complete transfer of stereochemical information in a Diels-Alder cycloaddition through a point-chirality, axial-chirality, point-chirality transfer process.


Subject(s)
Alkadienes/metabolism , Cycloaddition Reaction/methods , Catalysis , Humans , Stereoisomerism
15.
Nat Chem ; 10(9): 953-960, 2018 09.
Article in English | MEDLINE | ID: mdl-30061614

ABSTRACT

For over a century, the structures and reactivities of strained organic compounds have captivated the chemical community. Whereas triple-bond-containing strained intermediates have been well studied, cyclic allenes have received far less attention. Additionally, studies of cyclic allenes that bear heteroatoms in the ring are scarce. We report an experimental and computational study of azacyclic allenes, which features syntheses of stable allene precursors, the mild generation and Diels-Alder trapping of the desired cyclic allenes, and explanations of the observed regio- and diastereoselectivities. Furthermore, we show that stereochemical information can be transferred from an enantioenriched silyl triflate starting material to a Diels-Alder cycloadduct by way of a stereochemically defined azacyclic allene intermediate. These studies demonstrate that heteroatom-containing cyclic allenes, despite previously being overlooked as valuable synthetic intermediates, may be harnessed for the construction of complex molecular scaffolds bearing multiple stereogenic centres.


Subject(s)
Alkadienes/chemistry , Aza Compounds/chemistry , Cycloaddition Reaction , Density Functional Theory , Molecular Conformation , Stereoisomerism
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