Chiral saturated oxygen heterocycles are important components of bioactive compounds. Cyclization of alcohols onto pendant alkenes is a direct route to their synthesis, but few catalytic enantioselective methods enabling cyclization onto unactivated alkenes exist. Herein is reported a highly efficient copper-catalyzed cyclization of γ-unsaturated pentenols that terminates in C-C bond formation, a net alkene carboetherification. Both intra- and intermolecular C-C bond formations are demonstrated, yielding functionalized chiral tetrahydrofurans as well as fused-ring and bridged-ring oxabicyclic products. Transition state calculations support a cis-oxycupration stereochemistry-determining step.
Patients with generalized joint hypermobility (JHM) may experience excessive bruising/bleeding, with heavy menstrual bleeding (HMB) commonly reported. We performed a retrospective review of 30 adolescents seen in a Young Women's Hematology Clinic with both HMB and JHM. We found that (1) a significant delay (mean 36 months, range 5–72) occurred between menarche and referral to specialty care, (2) HMB had moderate to severe impact on school and physical activities in 60% of patients, and (3) most patients (68%) required escalation of their initial therapy. We suggest providers consider JHM as a risk factor for a more complex clinical course.
Chiral saturated oxygen heterocycles are important components of bioactive compounds. Cyclization of alcohols onto pendant alkenes is a direct route to their synthesis, but few catalytic enantioselective methods enabling cyclization onto unactivated alkenes exist. Herein is reported a highly efficient copper-catalyzed cyclization of γ-unsaturated pentenols that terminates in C-C bond formation, a net alkene carboetherification. Both intra-and intermolecular C-C bond formations are demonstrated, yielding functionalized chiral tetrahydrofurans as well as fused-ring and bridged-ring oxabicyclic products. Transition state calculations support a cis-oxycupration stereochemistry-determining step.
Objective To assess bleeding symptoms in patients with generalized/benign joint hypermobility (GJH), compare bleeding scores to healthy historical pediatric controls, and determine whether a correlation exists between Beighton scores and bleeding scores. Methods Patients with GJH ages 6–21 years seen by the rheumatology department at Nationwide Children's Hospital in Columbus, Ohio were eligible. Participants/guardians completed the International Society on Thrombosis and Haemostasis Bleeding Assessment Tool, a validated questionnaire defining the presence, severity, and frequency of bleeding symptoms. Scores of ≥3 have been associated with an underlying bleeding disorder in pediatric patients. Results Eighty‐one patients agreed to participate. The median age was 13 years (interquartile range 10–16 years), and the mean Beighton score was 6.3 (range 4–9). Commonly observed bleeding symptoms were oral bleeding (74%), easy bruising (59%), and bleeding with minor wounds (42%). Mean and median bleeding scores were 5.2 and 4, respectively, and were significantly higher than reported bleeding scores in pediatric controls, defined as those without bleeding symptoms or a previously diagnosed bleeding disorder (P < 0.001). Although 75% of patients (95% confidence interval 64–84) had an abnormal bleeding score, only 12.3% were previously assessed by hematology for bleeding symptoms. Among patients with GJH, higher Beighton scores were not associated with higher bleeding scores (Spearman's correlation –0.08). Conclusion In a cohort of pediatric patients with GJH, three‐fourths of participants had abnormal bleeding scores, with the mean bleeding score significantly elevated compared to healthy controls. We propose that screening for bleeding symptoms be integrated into routine care for GJH patients, with referral to hematology for patients with bleeding concerns.
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