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1.
Beilstein J Org Chem ; 20: 540-551, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440172

RESUMO

The present work covers novel herbicidal lead structures that contain a 2,3-dihydro[1,3]thiazolo[4,5-b]pyridine scaffold as structural key feature carrying a substituted phenyl side chain. These new compounds show good acyl-ACP thioesterase inhibition in line with strong herbicidal activity against commercially important weeds in broadacre crops, e.g., wheat and corn. The desired substituted 2,3-dihydro[1,3]thiazolo[4,5-b]pyridines were prepared via an optimized BH3-mediated reduction involving tris(pentafluorophenyl)borane as a strong Lewis acid. Remarkably, greenhouse trials showed that some of the target compounds outlined herein display promising control of grass weed species in preemergence application, combined with a dose response window that enables partial selectivity in certain crops.

2.
Bioorg Med Chem ; 27(24): 115142, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31685332

RESUMO

Novel synthetic lead structures interacting with RCAR/(PYR/PYL) receptor proteins were identified based on the results of a high-throughput screening campaign of a large compound library followed by focused SAR studies of the three most promising hit clusters. Whilst indolinylmethyl sulfonamides 8y,z and phenylsulfonyl ethylenediamines 9y,z showed strong affinities for RCAR/ (PYR/PYL) receptor proteins in wheat, thiotriazolyl acetamides 7f,s exhibited promising efficacy against drought stress in vivo (wheat, corn and canola) combined with confirmed target interaction in wheat and arabidopsis thaliana. Remarkably, binding affinities of several representatives of 8 and 9 were on the same level or even better than the essential plant hormone abscisic acid (ABA).


Assuntos
Ácido Abscísico/análogos & derivados , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/química , Ácido Abscísico/química , Ácido Abscísico/farmacologia , Produtos Agrícolas , Secas , Descoberta de Drogas , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Estrutura Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ligação Proteica , Sulfonamidas , Triticum/genética , Triticum/metabolismo
3.
Pest Manag Sci ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39104300

RESUMO

BACKGROUND: Weed control is a significant challenge for farmers around the globe. Of the various methods available for combatting weeds, small molecules remain the most effective and versatile technology to date. In the search for novel chemical entities with new modes of action toward herbicide-resistant weeds, we have investigated hexahydrofuro[3,4-b]furan-based acyl-acyl carrier protein (ACP) thioesterase inhibitors inspired by X-ray co-crystal structure-based modeling studies. RESULTS: By exploiting scaffold hopping concepts and molecular modeling studies we were able to identify new hexahydrofuro[3,4-b]furan-based lead structures showing promising activity in vivo against commercially important grass weeds in line with strong target affinity. CONCLUSION: The present work covers a series of novel herbicidal lead structures that possess a hexahydrofuro[3,4-b]furan scaffold as a structural key feature, carrying ortho-substituted aryloxy side chains. Based on an optimized synthetic approach a broad structure-activity relationship (SAR) study was carried out. The new compounds emerging from our modeling-inspired structural variations show good acyl-ACP thioesterase inhibition in line with promising initial herbicidal activity. Glasshouse trials showed that the hexahydrofuro[3,4-b]furans outlined herein display good control of cold and warm season grass-weed species in pre-emergence application. Remarkably, some of the novel acyl-ACP thioesterase-inhibitors also showed promising efficacy against warm season weeds that are difficult to control. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

4.
Pest Manag Sci ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334233

RESUMO

BACKGROUND: There are various methods to control weeds, that represent considerable challenges for farmers around the globe, although applying small molecular compounds is still the most effective and versatile technology to date. In the search for novel chemical entities with new modes-of-action that can control weeds displaying resistance, we have investigated two spirocyclic classes of acyl-ACP thioesterase inhibitors based on X-ray co-crystal structures and subsequent modelling studies. RESULTS: By exploiting scaffold-hopping and isostere concepts, we were able to identify new spirolactam-based lead structures showing promising activity in vivo against commercially important grass weeds in line with strong target affinity. CONCLUSION: The present work covers a series of novel herbicidal lead structures that contain a spirocyclic lactam as a structural key feature carrying ortho-substituted benzyl or heteroarylmethylene side chains. These new compounds show good acyl-ACP thioesterase inhibition in line with strong herbicidal activity. Glasshouse trials showed that the spirolactams outlined herein display promising control of grass-weed species in pre-emergence application combined with dose-response windows that enable partial selectivity in wheat and corn. Remarkably, some of the novel acyl-ACP thioesterase-inhibitors showed efficacy against resistant grass weeds such as Alopecurus myosuroides and Lolium spp. on competitive levels compared with commercial standards. © 2024 Society of Chemical Industry.

5.
Pest Manag Sci ; 79(6): 2264-2280, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36815643

RESUMO

BACKGROUND: Whilst there are several methods to control weeds, which continuously plague farmers around the globe, the application of small molecular compounds is still the most effective technology to date. Plants can evolve to become resistant to PPO-inhibitors, a class of herbicides in commercial use since the 1960s. It is therefore essential to continuously develop new herbicides based on this mode-of-action with enhanced intrinsic activity, an improved resistance profile and favourable physicochemical properties. Based on an Amaranthus PPO crystal structure and subsequent modelling studies, halogen-substituted pyrazoles have been investigated as isosteres of uracil-based PPO-inhibitors. RESULTS: By combining structural features from the commercial PPO-inhibitors tiafenacil and pyraflufen-ethyl and by investigating receptor-binding properties, we identified new promising pyrazole-based lead structures showing strong activity in vitro and in vivo against economically important weeds of the Amaranthus genus: A. retroflexus, and resistant A. palmeri and A. tuberculatus. CONCLUSION: The present work covers a series of novel PPO-inhibiting compounds that contain a pyrazole ring and a substituted thioacetic acid sidechain attached to the core phenyl group. These compounds show good receptor fit in line with excellent herbicidal activity against weeds that plague corn and rice crops with low application rates. This, in combination with promising selectivity in corn, have the potential to mitigate and affect weeds that have become resistant to some of the current market standards. Remarkably, some of the novel PPO-inhibitors outlined herein show efficacies against economically important weeds that were superior to recently commercialized and structurally related tiafenacil. © 2023 Society of Chemical Industry.


Assuntos
Herbicidas , Peste , Herbicidas/química , Protoporfirinogênio Oxidase , Pirazóis/farmacologia , Plantas Daninhas
6.
J Agric Food Chem ; 71(47): 18270-18284, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-37269295

RESUMO

There are several methods to control weeds, which impose particular challenges for farmers in all parts of the world, although applying small molecular compounds still remains the most efficient technology to date. However, plants can evolve to become resistant toward active ingredients which is also the case for protoporphyrinogen oxidase (PPO) inhibitors, a class of highly effective herbicides in use for more than 50 years. Hence, it is essential to continuously discover and develop new herbicidal PPO inhibitors with enhanced intrinsic activity, an improved resistance profile, enhanced crop safety, favorable physicochemical properties, and a clean toxicological profile. By modifying structural key features from known PPO inhibitors such as tiafenacil, inspired by isostere and mix&match concepts in combination with modeling investigations based on a wild-type Amaranthus crystal structure, we have found new promising lead structures showing strong activity in vitro and in vivo against several notorious dicotyledon and monocotyledon weeds with emerging resistance (e.g., Amaranthus palmeri, Amaranthus tuberculatus, Lolium rigidum, and Alopecurus myosuroides). While several phenyl uracils carrying an isoxazoline motif in their thio-linked side chain showed promising resistance-breaking potential against different Amaranthus species, introducing a thioacrylamide side chain afforded outstanding efficacy against resistant grass weeds.


Assuntos
Amaranthus , Herbicidas , Magnoliopsida , Protoporfirinogênio Oxidase/genética , Herbicidas/farmacologia , Plantas Daninhas , Poaceae , Resistência a Herbicidas
7.
Biomed Res Int ; 2020: 7571939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280703

RESUMO

Introduction. Mental illness and aggression are often seen as inextricably linked. There is a growing body of evidence on aggressive behavior towards others by people with schizophrenia. Even though there is no study conducted in this study area, this study will help to identify the factors associated with aggressive behavior to be dealt early and as a base line for further study. Therefore, this study was designed to determine the prevalence of aggressive behavior and associated factors among people with schizophrenia. METHOD: An institutional-based cross-sectional study was conducted at Ayder Comprehensive Specialized Hospital from May 6 to 31, 2019, among 403 participants who were selected by a systematic random sampling technique. Data was collected by an interview technique by using the Modified Overt Aggression Scale, entered and analyzed by using EPI-INFO version 3.5.3 and Statistical Package for Social Science version 20, respectively. The association between variables was analyzed using bivariate and multivariate logistic regression analyses, and the level of significance of association was determined at a P value < 0.05. RESULTS: A total of 403 schizophrenia patients were included making the response rate 95.4%. The prevalence of aggressive behavior was 26.6%. Significant associated factors for aggressive behavior were being male (AOR = 2.61, 95% CI (1.21, 5.61)), unemployment (AOR = 8.03, 95% CI (3.08, 25.95)), previous history of aggression (AOR = 6.22, 95% CI (2.75, 14.10)), psychotic symptoms (AOR = 8.12, 95% CI (3.11, 21.14)), drug nonadherence (AOR = 6.41, 95% CI (3.02, 13.63)), poor social support (AOR = 3.11, 95% CI (1.35, 7.17)), and alcohol use (AOR = 2.40, 95% CI (1.02, 5.66)). CONCLUSION: Prevalence of aggressive behavior is high among schizophrenia patients. Professionals have to identify clearly predictors of aggressive behavior giving special emphasis when treating male schizophrenia patients, who are unemployed, lack social support, with previous history of aggression, and alcohol users.


Assuntos
Agressão/psicologia , Esquizofrenia/epidemiologia , Adolescente , Adulto , Estudos Transversais , Etiópia/epidemiologia , Feminino , Hospitais , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , Tamanho da Amostra , Apoio Social , Fatores Socioeconômicos , Adulto Jovem
8.
Pediatr Radiol ; 35(5): 539-42, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15565339

RESUMO

We report on an infant with severe asphyxia and persistent pulmonary hypertension as a newborn. The baby received prolonged intravenous calcium gluconate therapy for hypocalcemia. At 5 weeks of age, multiple firm, indurated areas (armor-like lesions) were palpable in the subcutaneous tissues of the trunk, arms, legs, and face, particularly in skin folds. Roentgenographic study showed generalized soft-tissue calcifications throughout the body, extremities, and face. Calcinosis cutis occurs through a variety of pathogenetic mechanisms. Case reports on calcinosis cutis in infants are uncommon, and the calcifications are mostly localized. In our patient, they are generalized.


Assuntos
Calcinose/etiologia , Dermatopatias/etiologia , Asfixia Neonatal/complicações , Gluconato de Cálcio/efeitos adversos , Feminino , Seguimentos , Humanos , Hipocalcemia/tratamento farmacológico , Recém-Nascido , Síndrome da Persistência do Padrão de Circulação Fetal/complicações , Remissão Espontânea
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