ABSTRACT
Background: Today, cardiovascular, oncological, and neurodegenerative diseases are the main causes of death in the world, according to official World Health Organization (WHO) statistics. Antioxidants are used to treat and prevent these diseases. In order to develop optimal technology for obtaining drugs based on plant extracts with antioxidant action, it is necessary to determine the total antioxidant capacity of raspberry shoots. Objectives: The study aimed to determine the total antioxidant capacity of red raspberry shoots, study the content of biologically active substances (BAS), and the antioxidant activity of red raspberry shoot extracts obtained during subsequent exhaustive extraction. Methods: The number of phenolic compounds, catechins, flavonoids, and hydroxycinnamic acids was determined by a spectrophotometric analysis method, whereas organic acids were determined by the alkalimetric method in red raspberry shoot extracts; the antioxidant activity of obtained extracts was evaluated by potentiometric method. Results: The total antioxidant capacity of red raspberry shoots was 164.12 mmol-equiv./m dry weight, the sum of the total content of phenolic compounds was 24.40 mg gallic acid (GA)/mL, catechins 21.36 mg epigallocatechin-3-O-gallate (EGCG)/mL, flavonoids 0.77 mg rutin (R)/mL, hydroxycinnamic acids derivatives 2.56 mg chlorogenic acid (ChA)/mL and organic acids 1.88 mg citric acid (CA)/mL in red raspberry shoot extracts obtained during subsequent exhaustive extraction. The analysis showed that there is a very high positive correlation between antioxidant activity and total phenolic compounds, catechin, flavonoid, hydroxycinnamic acids derivatives, and organic acids content in red raspberry shoot extracts. Conclusions: Total red raspberry shoots' antioxidant capacity has been determined. The study results can be used to develop optimal technology for obtaining drugs based on the extract of red raspberry shoots, which has an antioxidant effect
Contexto: Hoy en día, las enfermedades cardiovasculares, oncológicas y neurodegenerativas son las principales causas de muerte en el mundo según estadísticas oficiales de la Organización Mundial de la Salud OMS. Los antioxidantes se utilizan para tratar y prevenir estas enfermedades. Para desarrollar una tecnología óptima para la obtención de fármacos a base de extractos de plantas con acción antioxidante, es necesario determinar la capacidad antioxidante total de los brotes de frambuesa.Objetivos: El estudio tuvo como objetivo determinar la capacidad antioxidante total de los brotes de frambuesa roja, estudiar el contenido de sustancias biológicamente activas (SBA) y la actividad antioxidante de los extractos de brotes de frambuesa roja obtenidos mediante extracción exhaustiva. Métodos: La cantidad de compuestos fenólicos, catequinas, flavonoides y ácidos hidroxicinámicos se determinó por método de análisis espectrofotométrico, mientras que los ácidos orgánicos por método alcalimétrico en extractos de brotes de frambuesa roja; La actividad antioxidante de los extractos obtenidos se evaluó por método potenciométrico. Resultados: La capacidad antioxidante total de los brotes de frambuesa roja fue de 164.12 mmol-equiv./m de peso seco, la suma del contenido total de compuestos fenólicos fue de 24.40 mg gálico ácido (GA)/mL, catequinas 21.36 mg epigalocatequina-3-O-galato (EGCG)/mL, flavonoides 0.77 mg rutina (R)/mL, derivados de ácidos hidroxicinámicos 2.56 mg clorogénico ácido (ChA)/mL y ácidos orgánicos 1.88 mg cítrico ácido (CA)/mL en extractos de brotes de frambuesa roja obtenidos durante extracción exhaustiva. La correlación analizada mostró que existe una correlación positiva entre la actividad antioxidante y el contenido de compuestos fenólicos totales, catequinas, flavonoides, derivados de ácidos hidroxicinámicos y ácidos orgánicos en extractos de brotes de frambuesa roja. Conclusiones: Gracias a nuestros resultados se ha determinado la capacidad antioxidante total de los brotes de frambuesa roja. Los resultados del estudio se pueden utilizar para desarrollar una tecnología óptima para la obtención de fármacos basados en el extracto de brotes de frambuesa roja, que tiene un efecto antioxidante
Subject(s)
Humans , Antioxidants , Phenols , Serial Extraction , Organic Acids , Correlation of DataABSTRACT
In accordance with the principles of "me-too" technique, the preparative method for obtaining has been proposed, and the synthesis of a large series of new N-(arylalkyl)-6-hydroxy-2-methyl-4-oxo-2,4-dihydro-1H-pyrrolo[3,2,1-ij]quinoline-5-carboxamides as structurally close analogs of tricyclic pyrrolo- and pyridoquinoline diuretics has been carried out. All target compounds were obtained with high yields and purity by amidation of ethyl ester of the corresponding 2-methyl-pyrroloquinoline-5-carboxylic acid with arylalkylamines in boiling ethanol. Their structure was confirmed by the data of elemental analysis, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry and polarimetry. Moreover, interpretations of their ¹H and 13C-NMR spectra, their mass spectrometric behavior, as well as peculiarities of the polarimetric studies were discussed. The effect of N-(arylalkyl)-6-hydroxy-2-methyl-4-oxo-2,4-dihydro-1H-pyrrolo[3,2,1-ij]quinoline-5-carboxamides on the urinary function of the kidneys was studied in white rats by the standard method of oral administration in the dose of 10 mg/kg compared to hydrochlorothiazide. According to the results of the primary pharmacological screening, the structural and biological regularities that were unexpected, but interesting for further studies were revealed. Among the substances studied, the samples, which by their diuretic effect are not inferior and even superior to both the known hydrochlorothiazide and the lead structure of the pyrroloquinoline group, have been found. On this basis, it can be argued that the introduction of the methyl group made by us in position 2 of pyrrolo[3,2,1-ij]quinoline nucleus can be considered as a successful and promising implementation of the "me-too" cloning of tricyclic 4-hydroxyquinoline-2-one diuretics.
ABSTRACT
Continuing a targeted search for new leading structures with diuretic action among tricyclic derivatives of hydroxyquinolines, which are of interest as potential inhibitors of aldosterone synthase, the synthesis of a series of the corresponding pyrido[3,2,1-ij]quinoline-6-carboxanilides was carried out by amidation of ethyl-7-hydroxy-5-oxo-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinoline-6-carboxylate with aniline, aminophenols and O-alkylsubstituted analogs with high yields and purity. The optimal conditions of this reaction are proposed; they make it possible to prevent partial destruction of the original heterocyclic ester and thereby avoid formation of specific impurities of 7-hydroxy-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinolin-5-one. To confirm the structure of all substances obtained, elemental analysis, nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry were used. Moreover, the peculiarities of their ¹H and 13C-NMR spectra, as well as their mass spectrometric behavior under conditions of electron impact ionization, were discussed. The effect of pyrido[3,2,1-ij]quinoline-6-carboxanilides on the urinary function of the kidneys was studied in white rats of both genders by the standard method of oral administration at a dose of 10 mg/kg. Testing was conducted in comparison with hydrochlorothiazide, as well as with structurally close pyrrolo[3,2,1-ij] quinoline-5-carboxanilides studied earlier with the same substituents in the anilide fragments. It was found that addition of one methylene unit to the heterocycle partially hydrogenated and annelated with the quinolone core has a positive impact on biological properties-most of the substances studied exhibit a statistically significant diuretic effect exceeding the activity of not only hydrochlorothiazide, in some cases, but also the action of the structural analogs. The important structural and biological regularities, which are common with pyrroloquinolines and introduced by a chemical modification, were revealed. The importance of the presence in the structure of terminal amide fragments of tricyclic quinoline-3-carboxamides of a 4-methoxy-substituted aromatic ring was particularly marked. The expediency of further study of pyridoquinolines as promising diuretic agents has been shown.
