Photocatalyst-free visible-light-promoted C(sp2)-P coupling: efficient synthesis of aryl phosphonates.

A novel and efficient method for the synthesis of aryl phosphonates from aryl halides and trialkylphosphites via EDA complex-based photochemistry has been developed. It is demonstrated that aryl radicals, generated from the photoexcitation of the EDA complex formed by aryl halide and potassium thioacetate, could be intercepted with trialkylphosphite to produce the corresponding aryl phosphonates in moderate to good yields. It should be noted that the reaction is performed at room temperature in the absence of any transition metal catalyst, oxidant and photocatalyst, exhibiting high efficiency, high selectivity, and operational simplicity.

Organocatalytic enantioselective cross-aldol reaction of aryl ketones with heteroaromatic trifluoromethyl ketone hydrates for the synthesis of α-trifluoromethyl tertiary alcohols.

An efficient organocatalytic enantioselective cross-aldol reaction of aryl ketones with heteroaromatic trifluoromethyl ketone hydrates via enolate intermediates has been developed. The cross-aldol reactions catalyzed by Takemoto-type thiourea catalysts proceeded well under mild conditions, furnishing a variety of enantioenriched α-trifluoromethyl tertiary alcohols bearing N-heteroaromatics with good to high yields and enantioselectivities. This protocol features broad substrate scope, good functional group tolerance, and easy gram-scale preparation.

Genetic Diversity and Pathogenic Variation of the Rice False Smut Pathogen Ustilaginoidea virens from Different Rice Cultivars.

Rice false smut, caused by Ustilaginoidea virens, has become one of the most devastating grain diseases of rice worldwide. Understanding the genetic diversity of U. virens is essential for efficient disease control and breeding for disease resistance. However, little is known about the genetic variation of U. virens from different rice cultivars. We investigated the genetic diversity and pathogenic variation of U. virens isolates from 10 rice cultivars in Zhejiang, China. A total of 260 polymorphic loci and 27 haplotypes were identified based on the 2,137-bp combined DNA fragments of all individuals; hap_4 was the most common haplotype, represented by 41 isolates. Phylogeny indicated that all isolates were divided into four genetic groups. Group I was the largest, with 98 isolates, distributed mainly in eight cultivar populations, whereas 90% of the isolates collected from a Changxiang cultivar were clustered in Group IV. Furthermore, the pairwise FST values exhibited significant genetic differentiation in 27 of the pairwise comparisons between populations, accounting for 23.21% of the total genetic variation. The genetic composition of the isolates of the CX population was distinguishable from that of the other nine populations, and genetic recombination was found in a few isolates. Finally, 27 haplotype representative isolates showed high variation in pathogenicity, and the isolates from the genetic subpopulation I were likely to be more virulent than those from genetic subpopulations II and III. Collectively, these findings suggest that differences in rice cultivars play an important role in the genetic variation of U. virens.

Porocarcinoma with orbital metastasis, a case report with review of literature.

We present a patient who presented with an orbital mass lesion which was a metastatic lesion from a porocarcinoma of the scalp with progressive deterioration of the patient.A 78-year-old male presented with functional decline and a rapidly growing scalp lesion of 3 months duration. In addition to the scalp lesion, Computed Tomography showed an incidental finding of a left lateral orbital wall tumour. Fine-needle aspiration of the two lesions revealed malignant cells with similar morphologies. Punch biopsy of the scalp lesion showed histological features suggestive of a porocarcinoma. Patient underwent palliative radiotherapy and immunotherapy and subsequently succumbed to the disease.

Direct Synthesis of Amides from Benzonitriles and Benzylic Alcohols via a KOt-Bu-Mediated MPV-type Hydrogen Transfer Process.

Meerwein-Ponndorf-Verley (MPV)-type reduction between benzonitriles and benzylic alcohols under transition-metal-free conditions has been demonstrated for the first time. Using simple KOt-Bu as the base, various benzonitriles can be efficiently reduced by benzylic alcohols via hydrogen transfer reduction, and the resultant phenyl imine can react further with benzylic alcohols to give amides as the final product in which both the alcohols and the nitriles are incorporated. Preliminary mechanistic investigations indicated that the reaction may go through multiple MPV-type hydrogen transfer processes.

Characterization of Genetic Diversity and Variation in Pathogenicity of the Rice False Smut Pathogen Ustilaginoidea virens from a Single Source.

Rice false smut, caused by Ustilaginoidea virens, is one of the most destructive fungal diseases in rice-growing countries. Studies of the genetic diversity, evolution, and pathogenicity of U. virens can provide more information for disease control and cultivar breeding. Contrary to previous studies on the genetic diversity of different geographical populations of U. virens, this study analyzed the genetic variation of U. virens from different panicles of the same rice cultivar in a field in Yunnan Province using single nucleotide polymorphism molecular markers. A total of 183 polymorphic loci and five haplotypes, hap_1 to hap_5, were identified based on the 1,350-bp combined DNA fragment of 127 isolates, showing some genetic diversity. Hap_1 and hap_3 had the highest occurrence, indicating they were the dominant haplotypes in the field. Further analysis showed that most rice panicles could be coinfected by different haplotypes, and even a few spikelets could be coinfected by multiple haplotypes. The phylogeny indicated that all isolates were divided into five genetic groups. Groups I, II, and III clustered together and were distinguished from Groups IV and V. Significant genetic variations in five pairwise comparisons of panicle populations, accounting for 72.45% of the total variation, were found according to FST values. This variation might be caused by different field microenvironments and the uneven distribution of inoculum sources. An unweighted pair-group method with arithmetic means dendrogram and the population structure revealed that the genetic composition of the isolates collected from YN1, YN2, and YN4, which were dominated by the same genetic subgroup, was different from that collected from YN3. Finally, genetic recombination was found in 11 isolates; hap_2 and hap_5, probably as genetic recombination progenies produced by sexual hybridization between hap_1 and hap_3, acquired a greater virulence than their ancestors according to population structure and pathogenicity analyses. These results will help us understand the genetic diversity, evolution, and infection process of U. virens and aid in the development of more effective management strategies for rice false smut, including new cultivars with improved resistance.

Genetic Diversity and Population Structure of the Rice False Smut Pathogen Ustilaginoidea virens in the Sichuan-Chongqing Region.

Rice false smut caused by Ustilaginoidea virens is one of the most devastating fungal diseases of rice panicles worldwide. In this study, two novel molecular markers derived from single nucleotide polymorphism-rich genomic DNA fragments and a previously reported molecular marker were used for analyzing the genetic diversity and population structure of 167 U. virens isolates collected from nine areas in the Sichuan-Chongqing region, China. A total of 62 haplotypes were identified, and a few haplotypes with high frequency were found and distributed in two to three areas, suggesting gene flow among different geographical populations. All isolates were divided into six genetic groups. Groups I and VI were the largest, with 61 and 48 isolates, respectively. The pairwise FST values showed significant genetic differentiation among all compared geographical populations. Analysis of molecular variance showed that intergroup genetic variation accounted for 40.17% of the total genetic variation, while 59.83% of genetic variation came from intragroup genetic variation. The unweighted pair-group method with arithmetic means dendrogram and population structure revealed that the genetic composition of isolates collected from Santai, Nanchong, Yongchuan, and Wansheng dominated by the same genetic subgroup was different from those collected from other areas. In addition, genetic recombination was found in a few isolates. These findings will help to improve the strategies for rice false smut management and resistance breeding, such as evaluating breeding lines with different isolates or haplotypes at different elevations and landforms.

Visible-light-promoted direct C3-trifluoromethylation and perfluoroalkylation of imidazopyridines.

An efficient method for direct trifluoromethylation and perfluoroalkylation at C3 of imidazopyridines through visible light-promoted C-H bond functionalization was developed. Under the irradiation of a blue LED, a series of C3-perfluoroalkyl-substituted imidazopyridines were synthesized from the corresponding imidazopyridines and perfluoroalkyl iodides in moderate to good yields at room temperature. It should be mentioned that this reaction proceeded in the absence of any transition-metal catalyst, oxidant and photocatalyst.

Predictors of mortality for patients with COVID-19 pneumonia caused by SARS-CoV-2: a prospective cohort study.

The aim of this study was to identify factors associated with the death of patients with COVID-19 pneumonia caused by the novel coronavirus SARS-CoV-2.All clinical and laboratory parameters were collected prospectively from a cohort of patients with COVID-19 pneumonia who were hospitalised to Wuhan Pulmonary Hospital (Wuhan City, Hubei Province, China) between 25 December 2019 and 7 February 2020. Univariate and multivariate logistic regression analysis revealed that age ≥65 years (OR 3.765, 95% CI 1.146­17.394; p=0.023), pre-existing concurrent cardiovascular or cerebrovascular diseases (OR 2.464, 95% CI 0.755­8.044; p=0.007), CD3+CD8+ T-cells ≤75 cells·µL−1 (OR 3.982, 95% CI 1.132­14.006; p<0.001) and cardiac troponin I ≥0.05 ng·mL−1 (OR 4.077, 95% CI 1.166­14.253; p<0.001) were associated with an increase in risk of mortality from COVID-19 pneumonia." has been corrected to: "Univariate and multivariate logistic regression analysis revealed that age ≥65 years (OR 3.765, 95% CI 1.201−11.803; p=0.023), pre-existing concurrent cardiovascular or cerebrovascular diseases (OR 2.464, 95% CI 1.279−4.747; p=0.007), CD3+CD8+ T-cells ≤75 cells·µL−1 (OR 3.982, 95% CI 1.761­9.004; p<0.001) and cardiac troponin I ≥0.05 ng·mL−1 (OR 4.077, 95% CI 1.778­9.349; p<0.001) were associated with an increase in risk of mortality from COVID-19 pneumonia. In a sex-, age- and comorbid illness-matched case-control study, CD3+CD8+ T-cells ≤75 cells·µL-1 and cardiac troponin I ≥0.05 ng·mL-1 remained as predictors for high mortality from COVID-19 pneumonia.We identified four risk factors: age ≥65 years, pre-existing concurrent cardiovascular or cerebrovascular diseases, CD3+CD8+ T-cells ≤75 cells·µL-1 and cardiac troponin I ≥0.05 ng·mL-1 The latter two factors, especially, were predictors for mortality of COVID-19 pneumonia patients.

Palladium-Catalyzed Formal Hydroalkylation of Aryl-Substituted Alkynes with Hydrazones.

We have developed an unprecedented Pd-catalyzed formal hydroalkylation of alkynes with hydrazones, which are generated in situ from naturally abundant aldehydes, as both alkylation reagents and hydrogen donors. The hydroalkylation proceeds with high regio- and stereoselectivity to form (Z)-alkenes, which are more difficult to generate compared to (E)-alkenes. The reaction is compatible with a wide range of functional groups, including hydroxy, ester, ketone, nitrile, boronic ester, amine, and halide groups. Furthermore, late-stage modifications of natural products and pharmaceutical derivatives exemplify its unique chemoselectivity, regioselectivity, and synthetic applicability. Mechanistic studies indicate the possible involvement of Pd-hydride intermediates.

Synthesis of Benzofulvenes via Cp*Co(III)-Catalyzed C-H Activation and Carbocyclization of Aromatic Ketones with Internal Alkynes.

A highly efficient and practical synthesis of benzofulvenes was developed via ketone-directed Cp*Co(III)-catalyzed sequential C-H activation, addition, cyclization, and dehydration cascade processes between simple aromatic ketones and alkynes. The reaction tolerates a variety of functional groups, and various benzofulvenes were efficiently synthesized in 42-92% yields.

Silver-Promoted Decarboxylative Sulfonylation of Aromatic Carboxylic Acids with Sodium Sulfinates.

A novel and efficient synthesis of sulfones was developed via a silver-promoted decarboxylative sulfonylation reaction between aromatic carboxylic acids and sodium sulfinates for the first time. The approach features operational simplicity and good functional group compatibility and uses readily available starting materials. Furthermore, mechanistic studies reveal that the decarboxylative sulfonylation reaction is likely to proceed via a radical mechanism.

Informative priors on fetal fraction increase power of the noninvasive prenatal screen.

PURPOSE: Noninvasive prenatal screening (NIPS) sequences a mixture of the maternal and fetal cell-free DNA. Fetal trisomy can be detected by examining chromosomal dosages estimated from sequencing reads. The traditional method uses the Z-test, which compares a subject against a set of euploid controls, where the information of fetal fraction is not fully utilized. Here we present a Bayesian method that leverages informative priors on the fetal fraction. METHOD: Our Bayesian method combines the Z-test likelihood and informative priors of the fetal fraction, which are learned from the sex chromosomes, to compute Bayes factors. Bayesian framework can account for nongenetic risk factors through the prior odds, and our method can report individual positive/negative predictive values. RESULTS: Our Bayesian method has more power than the Z-test method. We analyzed 3,405 NIPS samples and spotted at least 9 (of 51) possible Z-test false positives. CONCLUSION: Bayesian NIPS is more powerful than the Z-test method, is able to account for nongenetic risk factors through prior odds, and can report individual positive/negative predictive values.

Synthesis of Aryl Alkynes via Copper Catalyzed Decarboxylative Alkynylation of 2-Nitrobenzoic Acids.

An efficient protocol for the synthesis of internal aryl alkynes was achieved via Cu-catalyzed decarboxylative cross-coupling reactions, and to the best of our knowledge, this is the first example of a Cu-catalyzed decarboxylative alkynylation of benzoic acids with terminal alkynes. This approach utilizes simple Cu salt as catalyst and O2, an abundant, clean, and green material, as the oxidant. The reaction tolerates various functional groups, and a variety of internal aryl alkynes were synthesized in 46-83% yields.

Copper-catalyzed decarboxylative methylthiolation of aromatic carboxylate salts with DMSO.

A novel copper-catalyzed decarboxylative methylthiolation of arenecarboxylate salts has been realized using DMSO as the methylthiolation source. Various potassium aryl carboxylates underwent decarboxylative methylthiolation under air to furnish the corresponding aryl methyl thioethers in moderate to excellent yields. The reaction tolerated a wide variety of functional groups. Notably, the synthesis of ethylthioethers was also successfully achieved directly from diethyl sulfoxide under similar reaction conditions.

Synthesis of 4-benzylpyridines via Pd-catalyzed CH3-arylation of 4-picoline.

A highly efficient synthesis of 4-benzylpyridines was developed via Pd-catalyzed C(sp3)-H arylation between 4-picoline and aryl halides. It was found that the best yields were achieved with a simple Pd(PPh3)4 catalyst and Cs2CO3 as the base. Compared with the known methods, our reaction does not require the use of a strong organometallic reagent as the base.

Photocatalytic/Cu-Promoted C-H Activations: Visible-light-Induced ortho-Selective Perfluoroalkylation of Benzamides.

A visible-light-induced and copper-promoted perfluoroalkylation of benzamides was successfully developed under the assistance of an 8-aminoquinoline directing group. It provides a straightforward method for the synthesis of ortho-perfluoroalkyl-substituted benzoic acid derivatives. The reaction employs a cheap organic dye eosin Y as the photoredox catalyst and is run under the irradiation of a 26 W fluorescent LED light bulb.

HOTf-Catalyzed, Solvent-Free Oxyarylation of Ynol Ethers and Thioethers.

A novel HOTf-catalyzed oxyarylation of ynol ethers and thioethers has been realized with aryl sulfoxides as the oxyarylating reagents, providing α-arylated esters or thioesters in good to excellent yields. Notably, all atoms of the starting materials were incorporated in the product (100% atom economy) and the reaction proceeded under very mild conditions. It was found that the reaction can be ran under air and that the best yields are obtained under solvent-free conditions.

Cobalt-promoted selective arylation of benzamides and acrylamides with arylboronic acids.

A novel cobalt-promoted arylation of aryl C-H bonds with arylboronic acids has been realized by using 8-aminoquinoline as the directing group. The reaction tolerated a wide variety of functional groups and diversely substituted ortho-arylated benzamides were efficiently synthesized in good to excellent yields. Even though a catalytic amount of a Co-salt was enough to effect the transformation, better yields were obtained with a stoichiometric amount of the Co-salt. A notable feature of this newly developed protocol is that acrylamides, which cannot be arylated using copper salts as the promoter, can also be efficiently arylated. In addition, the stereochemistry of these arylation products can be largely retained under the standard conditions.