Design and Synthesis of Bicyclo[4.3.0]nonene Nucleoside Analogues

Nucleoside analogues are effective antiviral agents, and the continuous emergence of pathogenic viruses demands the development of novel and structurally diverse analogues. Here, we present the design and synthesis of novel nucleoside analogues with a carbobicyclic core, which mimics the conformation of natural ribonucleosides. Employing a divergent synthetic route featuring an intermolecular Diels-Alder reaction, we successfully synthesized carbobicyclic nucleoside analogues with high antiviral efficacy against respiratory syncytial virus.

Ni-Catalyzed 1,1- and 1,3-Aminoboration of Unactivated Alkenes

Alkene borylfunctionalization reactions have emerged as useful methods for chemical synthesis. While much progress has been made on 1,2-borylamination reactions, the related 1,1- and 1,3-borylaminations have not been reported. Herein, a Ni-catalyzed 1,1-borylamination of 1,1-disubstituted and monosubstituted alkenes and a 1,3-borylamination of cyclic alkenes are presented. Key to development of these reactions was the identification of an alkyllithium activator in combination with Mg salts. The utility of the products and the mechanistic details are discussed.

Catalytic Arylboration of Spirocyclic Cyclobutenes: Rapid Access to Highly Substituted Spiro[3.n]alkanes

A method to achieve the synthesis of highly substituted spirocyclic cyclobutanes is disclosed. The reaction involves the catalytic arylboration of cyclobutenes. Depending on the substitution pattern of the cyclobutene, either a Cu/Pd- or a Ni-catalyzed reaction was utilized. In the case of the Cu/Pd catalyzed reactions, the identification of a Cu-complex for arylboration was crucial to observe high selectivity. The synthetic utility of the products is demonstrated, and the mechanistic details are discussed.

Pivotal Reactions in the Creation of the Polycyclic Skeleton of Cryptotrione

Three pivotal reactions, namely, enyne cycloisomerization, polyene cyclization, and quinone methide formation, are applied to synthesize the complex polycyclic skeleton of cryptotrione. This review summarizes the most prominent applications of these three reactions to the total syntheses of natural products, covering results published in the literature between 2011 and 2020.

1 Introduction

2 Three Pivotal Reactions Applied to Create the Polycyclic Framework of Cryptotrione

2.1 Enyne Cycloisomerization

2.2 Polyene Cyclization

2.3 Quinone Methide Formation

3 Conclusion

Total Synthesis of Cryptotrione

The total synthesis of cryptotrione (1) was enabled by substrate-controlled diastereoselective construction of the bicyclo[3.1.0]hexene framework through platinum-catalyzed enyne cycloisomerization and Lewis acid induced polyene cyclization to construct the abietane-type tricyclic diterpene skeleton. The stereogenic tertiary carbon center in the side chain was installed in a diastereodivergent manner by conjugate addition reactions.

[Assessment of computed tomographic angiographysinus development combined with occipitalbone marks for the location of transverse sigmoid sinus junction]

Objective: To introduce and evaluate a technique to precisely localize the transverse-sigmoid sinus junction (TSSJ) in retrosigmoid craniotomy. Methods: This was a single-center prospective randomized controlled study. Sixty-three patients, 29 male and 34 female, who would undergo retrosigmoid craniotomy admitted to Department of Neurosurgery, the First Affiliated Hospital of Xinjiang Medical Universityfrom March to October 2019 were enrolled in the study and were divided into trial group and control group according to the computer-generated random numbers. Preoperative venous computed tomographic angiography (CTA) combined with 3-dimensional computed tomography computed tomography (3D CT) was randomly given to the patients(n=32). Asterion was used for identification of the TSSJ in the controls (n=31). The main outcome measures as postoperative complications and relevant intraoperative indicators were compared. Results: Incision length, craniotomy time, bone window sizein trial group were shorter or smaller than those of the controls, as(6.8±0.5) cm vs (8.0±1.5) cm, (37±8) min vs (45±15) min, (8.7±1.2) cm(2) vs (10.2±2.4) cm(2) respectively, with statistical significance (all P<0.05). No statistical significance was found in bleeding amount, incidence of sinus injury and cerebrospinal fluid leakage. While incidence of neck pain was lower in case group (15.63% vs 38.71%; P=0.04) and the remission time of incisional pain in case group was shorter [(6±1) d vs (9±2) d; P=0.01]. Conclusion: While the technique is used, the center of the keyhole should be located at transitional place of the lateral part of the occipitomastoid suture, the retromastoid ridge and the superior nuchal line. Compared with the traditional craniotomy method marked by asterion, it has great advantages in reducing incidence of postoperative complications, craniotomy time, and the remission time of incisional pain.

[Analysis of type C behavior in patients with oral lichen planus]

OBJECTIVE

To assess type C behavior in patients with oral lichen planus (OLP) in order to provide basis for clinical prevention, treatment and psychological intervention of OLP.

METHODS

Type C behavior scale was used on 85 OLP patients and 85 control patients, who were in accordance with the inclusion criteria, in order to investigate their type C behavior. The scale included 9 items: anxiety, depression, anger, anger toward inside (anger-in), anger toward outside (anger-out), reasoning, domination, optimism, and social support. Scores of the 9 items between OLP patients and control group were calculated under the instruction of the scale and were statistically analyzed, and OLP group was further stratified statistically by sex, reticulate-erosive-ulcerative (REU) pathological type and course of diseases, and the scores of each group were analyzed and compared.

RESULTS

Among the 85 OLP patients, there were more females, more non-erosive lesion type, and the most common site for OLP was the buccal mucosa. The scores of the type-C behavior questionnaire for anxiety, depression, anger and optimism were respectively 43.01±7.47, 44.02±7.61, 21.56±5.26, 22.15±4.00 among the OLP patients and were 37.94±8.70, 39.58±7.35, 18.12±5.39, 24.05±3.23 among control group, with significant differences(P<0.05 for all) between the two groups. The female OLP patients had higher anxiety, depression, anger scores (43.21±6.97, 44.29±7.54, 21.64±5.09) and lower reasoning, domination, optimism scores (39.12±5.66, 16.29±3.95, 22.05±4.12) with significant differences (P<0.05 for all) compared with those of the female controls. The scores between male patients and male controls showed no significant difference. The patients with erosive lesions had higher anger score (22.94±5.26) than that of the patients without erosive lesions(20.60±5.03), with a significant difference(P<0.05). With the development of the disease, the tendency of anxiety and depression of the patients were more obvious, while optimism scores remained declining. The patients suffering more than 3 years of OLP had higher anger-toward-outside scores (17.36±3.35) than the patients suffering less than 3 years of OLP (15.19±3.99), with a significant difference (P<0.05).

CONCLUSION

OLP patients showed an obvious type C behavior characteristic, especially in anxiety, depression, anger and low optimism. This research provides the C behavior characteristic of OLP for further psychological consultation or intervention during OLP treatment.