Search

Three series of scutellarein derivatives have been designed and synthesized based on metabolic mechanism of scutellarin ( 1) in vivo. Their thrombin inhibition activities were tested through the analyzation of prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen (FIB). The antioxidant activities of these target products were assessed by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) assay and the ability to protect PC12 cells against H2O2-induced cytotoxicity, and their solubilities were evaluated by ultraviolet (UV) spectrophotometer. The results showed that the two isopropyl groups substituted derivative ( 18c) demonstrated stronger anticoagulant activity, better water solubility, and good antioxidant activity compared with scutellarein ( 2), which warrants further development of 18c as a promising agent for ischemic cerebrovascular disease treatment. [ABSTRACT FROM AUTHOR]

Scutellarin, which is extracted from the dried plant of Erigeron breviscapus, has been reported to protect the neural injury against excitotoxicity induced by ischemia. However, there are a few studies on the protective effects of scutellarein, which is the main metabolite of scutellarin in vivo. Thus, this study investigated the neuroprotective effects of scutellarein on cerebral ischemia/reperfusion in rats by bilateral common carotid artery occlusion (BCCAO) model, through the analysis of endogenous amino acids using HILIC-MS/MS, and evaluation of Ca2+ concentration together with Ca2+-ATPase activity. The results showed that scutellarein having good protective effects on cerebral ischemia/reperfusion might by decreasing the excitatory amino acids, increasing the inhibitory amino acids, lowing intracellular Ca2+ level, and improving Ca2+-ATPase activity, which suggested that scutellarein might be a promising potent agent for the therapy of ischemic cerebrovascular disease. [ABSTRACT FROM AUTHOR]

An improved synthesis of 6-O-methyl-scutellarein is described. Benzyl bromide was selected to protect both the hydroxyl groups at C-4' and C-7 in scutellarein. The product was then methylated and deprotected to produce the target compound in high yield in four steps. [ABSTRACT FROM AUTHOR]

Scutellarin (1) possesses protective effects against neuronal injury, while 6-O-methyl-scutellarein (3), as the main metabolite of scutellarin in vivo, has not been reported about its protective effects previously. The present study mainly investigated whether the neural injury caused by ischemia/reperfusion would be influenced by different doses of 6-O-methyl-scutellarein (3). The results of behavioral, neurological, and histological examinations indicated that 6-O-methyl-scutellarein (3) could improve neuronal injury, and exhibit significant difference among the various doses. More importantly, 6-O-methyl-scutellarein (3) had better protective effects than scutellarin in rat cerebral ischemia. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a neurodegenerative disorder, which is complex and progressive; it has not only threatened the health of elderly people, but also burdened the whole social medical and health system. The available therapy for AD is limited and the efficacy remains unsatisfactory. In view of the prevalence and expected increase in the incidence of AD, the design and development of efficacious and safe anti-AD agents has become a hotspot in the field of pharmaceutical research. Due to the multifactorial etiology of AD, the multitarget-directed ligands (MTDLs) approach is promising in search for new drugs for AD. Tacrine, which is the first acetylcholinesterase (AChE) inhibitor, has been selected as the ideal active fragment because of its simple structure, clear activity, and its superiority in the structural modification, thus it could be introduced into the overall molecular skeletons of the multi-target-directed anti-AD agents. In this review, we have summarized the recent advances (2012 to the present) in the chemical modification of tacrine, which could provide the reference for the further study of novel multi-target-directed tacrine derivatives to treat AD. [ABSTRACT FROM PUBLISHER]

ContextScutellarin (1) has been widely used in China to treat acute cerebral infarction and paralysis induced by cerebrovascular diseases. However, scutellarin (1) has unstable metabolic characteristics. ObjectiveThe metabolic profile of 6-O-scutellarein was studied to determine its metabolic stabilityin vivo. Materials and methodsIn this study, a method of UFLC/Q-TOF MS was used to study the 6-O-methyl-scutellarein metabolites in rat plasma, urine, bile and faeces after oral administration of 6-O-methyl-scutellarein (3). One hour after oral administration of 6-O-methyl-scutellarein (3) (34 mg/kg), approximately 1 mL blood samples were collected in EP tubes from all groups. Bile, urine and faeces samples were collected from eight SD rats during 0–24 h after oral administration. The mass defect filtering, dynamic background subtraction and information dependent acquisition techniques were also used to identify the 6-O-methyl-scutellarein metabolites. ResultsThe parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces. The glucuronide conjugate of 6-O-methyl-scutellarein (M1,M2), diglucuronide conjugate of 6-O-methyl-scutellarein (M3), sulphate conjugate of 6-O-methyl-scutellarein (M4), glucuronide and sulphate conjugate of 6-O-methyl-scutellarein (M5), methylated conjugate of 6-O-methyl-scutellarein (M6) were detected in rat urine.M1,M2andM3were detected in rat bile.M1was found in rat plasma andM7was detected in faeces. Discussion and conclusionBecause the parent compound 6-O-methyl-scutellarein (3) was found in rat urine, plasma, bile and faeces, we speculate that 6-O-methyl-scutellarein (3) had good metabolic stabilityin vivo.This warrants further study to develop it as a promising candidate for the treatment of ischemic cerebrovascular disease. [ABSTRACT FROM PUBLISHER]

Scutellarin ( 1 ) could be hydrolyzed into scutellarein ( 2 ) in vivo and then converted into methylated, sulfated and glucuronidated forms. In order to investigate the biological activities of these methylated metabolites, eight methylated analogs of scutellarein ( 2 ) were synthesized via semi-synthetic methods. The antithrombotic activities of these compounds were evaluated through the analyzation of prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT) and fibrinogen (FIB). Their antioxidant activities were assessed by measuring their scavenging capacities toward 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and the ability to protect PC12 cells against H 2 O 2 -induced cytotoxicity. Furthermore, the physicochemical properties of these compounds including aqueous solubility and lipophilicity were also investigated. The results showed that 6- O -methylscutellarein ( 5 ) demonstrated potent antithrombotic activity, stronger antioxidant activity and balanced solubility and permeability compared with scutellarin ( 1 ), which warrants further development of 5 as a promising lead for the treatment of ischemic cerebrovascular disease. [ABSTRACT FROM AUTHOR]

In order to improve the biological activity and water solubility of scutellarin ( 1 ), some derivatives of its main metabolite (scutellarein) were designed and synthesized. All the compounds were tested for their thrombin inhibition activity through the analyzation of thrombin time (TT), activated partial thromboplastin time (APTT), prothrombin time (PT) and fibrinogen (FIB). Their antioxidant activities were assessed by measuring their scavenging capacities toward 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and the ability to protect PC12 cells against H 2 O 2 -induced cytotoxicity, their water solubility were also assessed by ultraviolet (UV) spectrophotometer. The results showed that compound 8b demonstrated stronger anticoagulant and antioxidant activity, better water solubility compared with scutellarein ( 2 ), which warrants it as a promising agent for the treatment of ischemic cerebrovascular disease. [ABSTRACT FROM AUTHOR]

O -Alkylated quercetin analogs were synthesized and their anticancer activities were assessed by a high-throughout screening (HTS) method. The structure–activity relationships (SAR) showed that introduction of long alkyl chain such as propyl group at the C-3 OH position or short alkyl chain such as ethyl group at the C-4′ OH position were very important for keeping inhibitory activities against the 16 cancer cell lines. Furthermore, when the two n -butyl groups were introduced into the C-3, C-7 or C-4′, C-7 positions, the anticancer activity was enhanced. [ABSTRACT FROM AUTHOR]