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1.
Genome Res ; 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948368

RESUMO

Understanding the genetic mechanisms of phenotypic variation in hybrids between domestic animals and their wild relatives may aid germplasm innovation. Here, we report the high-quality genome assemblies of a male Pamir argali (O ammon polii, 2n = 56), a female Tibetan sheep (O aries, 2n = 54), and a male hybrid of Pamir argali and domestic sheep, and the high-throughput sequencing of 425 ovine animals, including the hybrids of argali and domestic sheep. We detected genomic synteny between Chromosome 2 of sheep and two acrocentric chromosomes of argali. We revealed consistent satellite repeats around the chromosome breakpoints, which could have resulted in chromosome fusion. We observed many more hybrids with karyotype 2n = 54 than with 2n = 55, which could be explained by the selfish centromeres, the possible decreased rate of normal/balanced sperm, and the increased incidence of early pregnancy loss in the aneuploid ewes or rams. We identified genes and variants associated with important morphological and production traits (e.g., body weight, cannon circumference, hip height, and tail length) that show significant variations. We revealed a strong selective signature at the mutation (c.334C > A, p.G112W) in TBXT and confirmed its association with tail length among sheep populations of wide geographic and genetic origins. We produced an intercross population of 110 F2 offspring with varied number of vertebrae and validated the causal mutation by whole-genome association analysis. We verified its function using CRISPR-Cas9 genome editing. Our results provide insights into chromosomal speciation and phenotypic evolution and a foundation of genetic variants for the breeding of sheep and other animals.

2.
Chemistry ; 30(50): e202402085, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38926940

RESUMO

We described a copper(I)-catalyzed atom economic and selective hydroamination-cyclization of alkynyl-tethered quinazolinones to prepare a variety of indole-fused pyrazino[1,2-a]quinazolinones in good to excellent yields ranging from 39 %-99 % under mild reaction conditions. Control experiments revealed that coordination-directed method of quinazolinone moiety with copper(I) was important for the selective hydroamination-cyclization of alkynes at the N1-atom instead of N3-atom of quinazolinone. The reaction could be easily performed at gram scales and some prepared indole-fused pyrazino[1,2-a]quinazolinones with donating groups on the indole moiety showed a distinct fluorescence emission wavelength with blue shift under the acid conditions.

3.
Org Biomol Chem ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39434558

RESUMO

We described a chiral phosphoric acid (CPA) catalyzed asymmetric [3 + 3] cycloaddition of cinnamaldehyde-derived N-aryl nitrones with 2-indolylmethanols to prepare various indole-fused 1,2-oxazines in high yields (up to 96%) with excellent enantioselectivity (>99% ee). Control experiments indicate that hydrogen bonding plays important roles in controlling the enantioselectivity of products. This strategy provides an efficient pathway to construct enantioenriched indole-fused 1,2-oxazines from N-aryl nitrones with 2-indolylmethanols.

4.
Org Biomol Chem ; 22(7): 1386-1390, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38276964

RESUMO

A variety of 4-(trichloromethyl)pyrido[2',1':3,4]pyrazino[2,1-b]quinazolinones were prepared in moderate to good yields with high regioselectivity through intramolecular 6-endo-dig cyclization and trichloromethylation of N3-alkynyl-2-pyridinyl-tethered quinazolinones in chloroform. Mechanistic studies revealed that chloroform might serve as a trichloromethyl anion precursor. Furthermore, the reaction could be easily performed on gram scales and an estrone-derived 4-(trichloromethyl)pyrido[2',1':3,4]pyrazino[2,1-b]quinazolinone was prepared over five steps. The present method features broad substrate scope, good functional group tolerance, new dearomatization of pyridine rings, and chloroform as the trichloromethylation reagent.

5.
Bioorg Chem ; 143: 107015, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086241

RESUMO

Conventional topoisomerase (Topo) inhibitors typically usually exert their cytotoxicity by damaging the DNAs, which exhibit high toxicity and tend to result in secondary carcinogenesis risk. Molecules that have potent topoisomerase inhibitory activity but involve less DNA damage provide more desirable scaffolds for developing novel chemotherapeutic agents. In this work, we broke the rigid pentacyclic system of luotonin A and synthesized thirty-three compounds as potential Topo inhibitors based on the devised molecular motif. Further investigation disclose that two compounds with the highest antiproliferation activity against cancer cells, 5aA and 5dD, had a distinct Topo I inhibitory mechanism different from those of the classic Topo I inhibitors CPT or luteolin, and were able to obviate the obvious cellular DNA damage typically associated with clinically available Topo inhibitors. The animal model experiments demonstrated that even in mice treated with a high dosage of 50 mg/kg 5aA, there were no obvious signs of toxicity or loss of body weight. The tumor growth inhibition (TGI) rate was 54.3 % when 20 mg/kg 5aA was given to the T24 xenograft mouse model, and 5aA targeted the cancer tissue precisely without causing damage to the liver and other major organs.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Animais , Camundongos , Antineoplásicos/farmacologia , Quinonas , Pirróis , Inibidores da Topoisomerase I/farmacologia , Inibidores da Topoisomerase I/uso terapêutico , Dano ao DNA , DNA Topoisomerases Tipo I/metabolismo , Inibidores da Topoisomerase II/farmacologia , DNA Topoisomerases Tipo II , Linhagem Celular Tumoral
6.
Bioorg Chem ; 152: 107716, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39178707

RESUMO

Lycodine alkaloids are important natural products with diverse biological effects. In this manuscript, we set out the first structural optimization of the 2-pyridone moiety of Lycodine alkaloid via selective O-arylation under metal-free conditions and obtained a series of potent bioactive molecules against monosodium urate (MSU)-induced IL-1ß production. Further investigations demonstrated that these natural product derivatives could activate the neuro-immunomodulatory cholinergic anti-inflammatory pathway (CAP) to block the initial phase of NLRP3 inflammasome activation. Compared with the clinical drugs hydrocortisone and indomethacin, as well as commercially available CAP agonists GTS-21 and pnu282987, 3k and 3q possessed greater potency against MSU-induced IL-1ß production. Meanwhile, these molecules possessed less cytotoxicity against promonocytic THP-1 macrophages when compared with colchicine. This work reports a concise strategy for direct modification of 2-pyridone moiety from natural Lycodine alkaloids, and provides novel frameworks for discovering CAP activators and drugs for gout arthritis.


Assuntos
Artrite Gotosa , Humanos , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/síntese química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/síntese química , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/síntese química , Artrite Gotosa/tratamento farmacológico , Relação Dose-Resposta a Droga , Interleucina-1beta/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade
7.
J Org Chem ; 88(23): 16155-16166, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37975833

RESUMO

A variety of spirooxindole-1,2-oxazinan-5-one derivatives were prepared in moderate to excellent yields through 2,2,2-trifluoroethanol (TFE)-promoted [3 + 3] cycloaddition of N-vinyl oxindole nitrones with oxyallyl cations generated from α-tosyloxy ketones under mild reaction conditions. Mechanistic studies revealed that [3 + 3] cycloaddition might involve two possible reaction pathways, including direct [3 + 3] cycloaddition of N-vinyl oxindole ntirones with oxyallyl cations, or the addition of TFE to N-vinyl oxindole nitrones, sequential addition to oxyallyl cations, elimination, and cyclization. The present method features mild reaction conditions, broad substrate scope, good functional group tolerance, easy gram scalable preparation, and new applications of TFE.

8.
J Org Chem ; 88(1): 690-700, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36485009

RESUMO

A variety of tetrahydro-5H-indolo[2,3-b]quinolines were prepared in 40-97% yields through a copper(II)-catalyzed cascade reaction of aza-o-quinone methides generated in situ from 2-(chloromethyl)anilines and indoles. Experimental results showed that the reaction underwent double 1,4-additions and sequential intramolecular cyclization. The present method features broad substrate scope, good functional group tolerance, and easy gram scalable preparation of indolo[2,3-b]quinolines.


Assuntos
Indóis , Quinolinas , Indóis/química , Estrutura Molecular , Cobre/química , Quinolinas/química , Catálise
9.
Bioorg Chem ; 138: 106611, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37236073

RESUMO

Pseudo-natural products (PNPs) design strategy provides a great valuable entrance to effectively identify of novel bioactive scaffolds. In this report, novel pseudo-rutaecarpines were designed via the combination of several privileged structure units and 46 target compounds were synthesized. Most of them display moderate to potent inhibitory effect on LPS-induced NO production and low cytotoxicity in RAW264.7 macrophage. The results of the anti-inflammatory efficacy and action mechanism of compounds 7l and 8c indicated that they significantly reduced the release of IL-6, IL-1ß and TNF-α. Further studies revealed that they can strongly inhibit the activation of NF-κB and MAPK signal pathways. The LPS-induced acute liver injury mice model studies not only confirmed their anti-inflammatory efficacy in vivo but also could effectively relieve the liver injury in mice. The results suggest that compounds 7l and 8c might serve as lead compounds to develop therapeutic drugs for treatment of inflammation.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Camundongos , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia , Células RAW 264.7 , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Fígado/metabolismo
10.
Biochem Genet ; 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910330

RESUMO

Leukoaraiosis (LA) appears as white matter hyperintensities on T2-weighted brain magnetic resonance imaging scans. Age and hypertension are considered the primary risk factors for LA, but its pathogenesis remains uncertain. This study aims to investigate the correlation between the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and LA. A total of 140 patients with LA and 136 neuroimaging alteration-free controls were recruited in a case-control study. ACE I/D polymorphism was determined using the polymerase chain reaction method. The allele and genotype distributions of the ACE I/D polymorphism were significantly different between subjects with and without LA. Significant difference was observed in the genotypic distribution between LA patients and controls for recessive and additive models. A statistically significant association remained apparent after adjusting for potential risk factors (D/D vs. I/D + I/I: adjusted OR 3.251, 95% CI 1.185-8.918; D/D vs. I/I: adjusted OR 3.277, 95% CI 1.187-9.047). Our results indicate that the D/D genotype and D allele are important risk factors for LA. Future studies with larger populations are needed to validate our results.

11.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37050567

RESUMO

In this study, the design of a Digital-twin human-machine interface sensor (DT-HMIS) is proposed. This is a digital-twin sensor (DT-Sensor) that can meet the demands of human-machine automation collaboration in Industry 5.0. The DT-HMIS allows users/patients to add, modify, delete, query, and restore their previously memorized DT finger gesture mapping model and programmable logic controller (PLC) logic program, enabling the operation or access of the programmable controller input-output (I/O) interface and achieving the extended limb collaboration capability of users/patients. The system has two main functions: the first is gesture-encoded virtual manipulation, which indirectly accesses the PLC through the DT mapping model to complete control of electronic peripherals for extension-limbs ability by executing logic control program instructions. The second is gesture-based virtual manipulation to help non-verbal individuals create special verbal sentences through gesture commands to improve their expression ability. The design method uses primitive image processing and eight-way dual-bit signal processing algorithms to capture the movement of human finger gestures and convert them into digital signals. The system service maps control instructions by observing the digital signals of the DT-HMIS and drives motion control through mechatronics integration or speech synthesis feedback to express the operation requirements of inconvenient work or complex handheld physical tools. Based on the human-machine interface sensor of DT computer vision, it can reflect the user's command status without the need for additional wearable devices and promote interaction with the virtual world. When used for patients, the system ensures that the user's virtual control is mapped to physical device control, providing the convenience of independent operation while reducing caregiver fatigue. This study shows that the recognition accuracy can reach 99%, demonstrating practicality and application prospects. In future applications, users/patients can interact virtually with other peripheral devices through the DT-HMIS to meet their own interaction needs and promote industry progress.


Assuntos
Gestos , Dispositivos Eletrônicos Vestíveis , Humanos , Interface Usuário-Computador , Dedos , Algoritmos
12.
Org Biomol Chem ; 20(32): 6293-6313, 2022 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-35838160

RESUMO

As one of the most important structural units in pharmaceuticals and medicinal chemistry, quinazolinone and its derivatives exhibit a wide range of biological and pharmacological activities, including anti-inflammatory, antitubercular, antiviral, and anticancer activities, etc. In particular, 2,3-fused quinazolinones have attracted much attention because the rings fused to the 2,3-positions of quinazolinones improve their rigidity and planarity. Their synthetic strategies have made great advances in recent years. Therefore, this review focuses on novel strategies for the synthesis of 2,3-fused quinazolinone derivatives from 2017 to 2022, such as the difunctionalization of alkenes, the ring-opening of easily available small rings, dehydrogenative cross-coupling reactions, transition-metal catalyzed cyclizations, cycloadditions, and other cascade reactions.


Assuntos
Química Farmacêutica , Quinazolinonas , Reação de Cicloadição , Quinazolinonas/química
13.
Org Biomol Chem ; 20(8): 1656-1661, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35156988

RESUMO

A variety of functionalized sulfonium ylides were prepared in good yields through MnSO4-promoted S-O bond cleavage from activated alkynes and sulfoxides. Experimental results showed that the MnSO4 catalyst played important roles in accelerating the reaction and promoting the [1,3]-rearrangement of the S-O bond. Furthermore, the product was easily obtained on a gram scale by simple recrystallization without column chromatography. The obtained product can be converted to new sulfonium ylides and undergo cycloaddition with an alkyne to afford a trisubstituted furan scaffold.

14.
Org Biomol Chem ; 20(10): 2069-2074, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35201247

RESUMO

A variety of functionalized spiroindolenine-3,3'-pyrrolo[2,1-b]quinazolinones were prepared in good to excellent yields through a gold(I)-catalyzed dearomative cyclization of N-alkynyl quinazolinone-tethered C2-substituted indoles. This reaction features a broad substrate scope, good functional group tolerance, and easy gram-scale preparation and transformations. Furthermore, biological activity studies showed that most of the obtained spiroindolenine-3,3'-pyrrolo[2,1-b]quinazolinone scaffolds showed potential as good anti-inflammatory agents.

15.
Mamm Genome ; 32(2): 115-122, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33755782

RESUMO

Atherosclerosis was an important pathophysiological basis of atherothrombotic stroke, and phosphodiesterase 4D (PDE4D) polymorphism (SNP83/rs966221) was reported to be associated with the susceptibility to atherothrombotic stroke. Aim of the present study was to explore the potential association between SNP83 and carotid atherosclerosis (CAS). 204 southern Chinese Han participants were divided into two groups according to the carotid intima-media thickness (IMT) of the carotid artery: CAS group (carotid IMT ≥ 1.0 mm) and non-CAS group (carotid IMT < 1.0 mm). Carotid IMT was measured by color Doppler ultrasound. The PDE4D SNP83 polymorphism was determined by SNaPshot technique. Our study found that SNP83 was associated significantly with CAS susceptibility under the dominant, overdominant and codominant models. After adjusting for age, gender, low-density lipoprotein cholesterol, Hemoglobin A1c, cigarette smoking, hypertension history, and diabetes mellitus history, the association still remained significant (dominant model: crude OR = 2.373, 95% CI: 1.268-4.442, P = 0.007; adjusted OR = 3.129, 95% CI: 1.104-8.866, P = 0.032; overdominant model: crude OR = 1.968, 95% CI: 1.043-3.714, P = 0.037; adjusted OR = 2.854, 95% CI: 1.005-8.108, P = 0.049; codominant: crude OR = 2.102, 95% CI: 1.110-3.979, P = 0.023; adjusted OR = 2.984, 95% CI: 1.047-8.502, P = 0.041). Carotid IMT of carriers with CT + CC genotypes was higher than carriers with TT genotype (P = 0.016). Our results indicated that the SNP83/rs966221 located on PDE4D gene was significantly associated between CAS susceptibility and carotid IMT independently of conventional risk factors in a southern Chinese Han population.


Assuntos
Povo Asiático/genética , Doenças das Artérias Carótidas/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Alelos , Biomarcadores , Doenças das Artérias Carótidas/diagnóstico , Espessura Intima-Media Carotídea , China , Estudos de Associação Genética , Genótipo , Humanos , Fatores de Risco
16.
Org Biomol Chem ; 19(15): 3379-3383, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33899889

RESUMO

A variety of tetrahydroquinoline-fused bicycles bearing multiple stereocenters are prepared in good yields with high diastereoselectivity through Cu2O-catalyzed [4 + 2] cycloaddition of aza-ortho-quinone methides (ao-QMs) with bicyclic alkenes. Mechanistic studies reveal that the Cu(i) catalyst not only promotes the formation of ao-QMs through a radical process by single electron transfer but also accelerates [4 + 2] cycloaddition. The reaction was easily performed on gram scale and the obtained tetrahydroquinoline-fused bicycles can be converted to diverse tetrahydroquinoline scaffolds.

17.
Bioorg Chem ; 114: 105101, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34175723

RESUMO

Thirty-eight new 3-arylaminoquinoxaline-2-carboxamide derivatives were in silico designed, synthesized and their cytotoxicity against five human cancer cell lines and one normal cells WI-38 were evaluated. Molecular mechanism studies indicated that N-(3-Aminopropyl)-3-(4-chlorophenyl) amino-quinoxaline-2-carboxamide (6be), the compound with the most potent anti-proliferation can inhibit the PI3K-Akt-mTOR pathway via down regulating the levels of PI3K, Akt, p-Akt, p-mTOR and simultaneously inhibit the phosphorylation of Thr308 and Ser473 residues in Akt kinase to servers as a dual inhibitor. Further investigation revealed that 6be activate the P53 signal pathway, modulated the downstream target gene of Akt kinase such p21, p27, Bax and Bcl-2, caused the fluctuation of intracellular ROS, Ca2+ and mitochondrial membrane potential to induce cell cycle arrest and apoptosis in MGC-803 cells. 6be also display moderate anti-tumor activity in vivo while displaying no obvious adverse signs during the drug administration. The results suggest that 3-arylaminoquinoxaline-2-carboxamide derivatives might server as new scaffold for development of PI3K-Akt-mTOR inhibitor.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Quinoxalinas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinoxalinas/síntese química , Quinoxalinas/química , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/metabolismo
18.
J Org Chem ; 85(5): 3059-3070, 2020 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-31958946

RESUMO

An approach for the construction of furo[3,2-b]quinolines and furo[2,3-b:4,5-b']diquinolines is developed through a metal-free [4 + 2] cycloaddition of easily available in situ generated aza-o-quinone methides and furans. The reaction tolerates a wide range of aza-o-quinone methides and substituted furans to afford the corresponding dihydro- or tetrahydrofuroquinolines in good to excellent yields. Mechanistic studies reveal that the reaction involves a concerted [4 + 2] cycloaddition pathway and shows a high regioselectivity of cycloaddition for a furan ring. The present method features mild reaction conditions, dearomatization of furans, high regio- and diastereoselectivity, gram-scalable preparations, and diversity of furoquinolines.

19.
Org Biomol Chem ; 18(40): 8209-8218, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33043956

RESUMO

Various α-aminooxy amides bearing a quaternary carbon at the α-position were prepared in good to excellent yields under mild reaction conditions from N-vinyl nitrones and α-bromohydroxamates. The N-vinyl nitrones tolerate a wide range of N-vinyl fluorenone nitrones and N-vinyl isatin nitrones. Mechanistic studies show that the reaction initially proceeds through [3 + 3] cycloaddition between N-vinyl nitrones and aza-oxyallyl cations generated from α-bromohydroxamates to afford six-membered N,O-heterocycles, followed by double C-N bond cleavage in the presence of the Sc(OTf)3 catalyst. A selective N-O bond cleavage of the obtained α-aminooxy amides is also realized under Fe/NH4Cl conditions. Furthermore, gram-scalable preparations of α-aminooxy amides are easily achieved.

20.
J Org Chem ; 84(16): 9859-9868, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31347845

RESUMO

An atom-economical and practical method for the efficient synthesis of various pyrazino[1,2-a]indole-2-oxides was developed through a nickel(II)-catalyzed [5 + 1] annulation of 2-carbonyl-1-propargylindoles with hydroxylamine in water without using an organic solvent. The reaction involved an initial condensation of 2-carbonyl-1-propargylindoles with hydroxylamine to afford oxime intermediates, which then underwent a nickel(II)-catalyzed 6-exo-dig cyclization. Preliminary studies showed that (n-Bu)4NI served as a phase transfer catalyst and promoted the formation of active nickel(II) species. More importantly, the nickel(II) salt and phase transfer catalyst-in-water could be recycled seven times, and a gram scalable product was easily obtained in good yields through a filtration and washing protocol.

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