Omphalane diterpenoids usually contain a cyclohexane-fused bicyclo[3.2.1]octane scaffold embedded with two continuous quaternary carbon centers, which pose considerable challenges to synthetic chemists.
View Article and Find Full Text PDFObjective: To observe the effect of warm needle with moxibustion (WNM) on morphological changes of articular cartilage and subchondral bone tissues in knee osteoarthritis (KOA) rabbits, so as to explore whether WNM intervention can delay the development of KOA.
Methods: Forty male New Zealand rabbits were randomly divided into blank control, model, WNM and medication (Alendronate sodium) groups, with 10 rabbits in each group. A KOA model was established by immobilizing the right hind limb of rabbits with orthopedic casting tape for 6 weeks.
Conformation is one of the most fundamental concepts in organic chemistry for chemists to visualize a molecule as a three-dimensional object in addition to its constitution and configuration. Conformational factors significantly affect the physical properties, chemical reactivities, and biological activities of a molecule. The significance of conformational design has been generally recognized since its successful application in the total synthesis of complex natural products, such as vitamin B12 and erythronolide.
View Article and Find Full Text PDFOrg Biomol Chem
February 2020
Aplydactone is a brominated sesquiterpene isolated from the sea hare Aplysia dactylomela. Structurally, it features a complex cage-like skeleton containing a highly strained tricyclic-[4.2.
View Article and Find Full Text PDFAn intriguing cage-like polyhemiketal, nesteretal A (), was isolated from the coral-derived actinomycete . Its structure was established by extensive spectroscopic and computational methods. Nesteretal A is a highly oxygenated compound featuring an unprecedented 5/5/5/5 tetracyclic scaffold.
View Article and Find Full Text PDFIEEE Trans Cybern
December 2018
Rather than a whole Pareto-optimal front, which demands too many points (especially in a high-dimensional space), the decision maker (DM) may only be interested in a partial region, called the region of interest (ROI). In this case, solutions outside this region can be noisy to the decision-making procedure. Even worse, there is no guarantee that we can find the preferred solutions when tackling problems with complicated properties or many objectives.
View Article and Find Full Text PDFThe first total synthesis of (+)-majusculoic acid, the enantiomer of naturally occurring antifungal cyclopropane fatty acid (-)-majusculoic acid, was accomplished in 13 steps, leading to the assignment of the absolute configuration of the natural product. The synthesis featured a ring closing metathesis dimerization, a conformationally controlled cyclopropanation, a dedimerization, and a bromoolefination.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
July 2017
A concise, protecting-group-free total synthesis of the unusual brominated sesquiterpene aplydactone is described. Our synthesis features a [2+2] photocycloaddition, a Wolff ring contraction, an unusual remote C-H functionalization to establish the highly strained tetracyclic core, and a hydrogen-atom transfer (HAT) reaction to access the bromine-containing stereocenter. A finely tuned conformation of the α-diazoketone precursor is the key for the success of the late-stage transannular C-H insertion to deliver a bridged six-membered ring and a quaternary stereocenter (C6) between two quaternary carbon atoms (C1 and C7).
View Article and Find Full Text PDFSichuan Da Xue Xue Bao Yi Xue Ban
March 2016
Objective: To explore the comorbidity mechanism of asthma and depression.
Methods: A self-developed questionnaire, which also contained Asthma Control Test (ACT), Asthma Quality of Life Questionnaire (AQLQ) and Hamilton Rating Scale for depression ( HRSD), was administered in 41 participants with asthma (AS), asthma and depression (AD), or none any of these conditions (health control, HC). Lung function and blood levels of eosnophils and IgE were also detected in those in the AS and AD groups.
Asian Pac J Allergy Immunol
June 2016
Background: Interleukin-17A (IL-17A), a proinflammatory cytokine, plays an important role in the pathogenesis of asthma. Considerable research has assessed the association between IL-17A polymorphisms and asthma risk, but the results are inconsistent.
Objective: This meta-analysis was carried out to make a more precise estimation of the relationship between IL-17A polymorphisms and asthma risk.
Allergy Asthma Proc
December 2016
Background: The prevalence of psychological symptoms such as anxiety and depression among patients with asthma is high. Both asthma and psychological symptoms are characterized by immune inflammation in which CD4+ T cells play a role.
Objective: To investigate whether T-helper (Th) 1, Th2, and Th17 cells imbalance exists in patients with asthma and with and in patients without psychological symptoms.
A concise, asymmetric total synthesis of (+)-fusarisetin A, a hybrid natural product, has been achieved. A one-pot four-reaction process efficiently delivered the tetracycle 2 which served as a key intermediate for the synthesis of the title natural product and its analogues through amino acid incorporation.
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