Fluorescence emission after two-photon absorption of coumarins and xanthenes in an alcoholic solution was measured in the tuning range of a femtosecond-pulsed titanium-sapphire laser (750-840 nm). Xanthenes, which have a low one-photon absorption in the near UV, show a higher fluorescence signal after two-photon absorption than the UV-excitable coumarins. When fluxes of 10(28) photons/(cm(2) s)...

Coumarins are classified as a member of the benzopyrone family. all of which consist of a benzene ring joined to a pyrone ring. The benzopyrones can be subdivided into the benzoalfa-pyrones to which the coumarins belong and the benzo-gama-pyrones, of which the flavonoids are principal members. Umbelliferone, esculetin and scopoletin are the most widespread coumarins in nature. During the synthe...

Pd-catalyzed oxidative Heck reactions of coumarins were developed via simultaneous C-H functionalization at the C3 position of coumarins under aerobic conditions.

Introduction: Parthenium hysterophorus is a plant used in traditional medicine to treat health issues and which could be source of phytochemicals with possible antioxidant activity without causing cytotoxic effects. Hence, this work was designed evaluate its phytochemical profile, cytotoxicity, activity. Methods: The aqueous (AE) ethanolic (EE) extracts P. flowers were obtained by decoction ult...

1. Abstract 2. Introduction 3. Phytoalexins and cancer prevention mechanisms 3.1. Antimicrobial activity 3.2. Proliferation 3.2.1. Cruciferous phytoalexins 3.2.2. Deoxyanthocyanidins 3.2.3. Glycoalkaloids 3.2.4. Stilbenes 3.2.5. Phenolic coumarins and garlic phytoalexins 3.3. Apoptosis 3.3.1. Stilbenes 3.3.2. Phenolic coumarins 3.3.3. Glycoalkaloids 3.3.4. Garlic phytoalexins 3.3.5. Di-terpenes...

Coumarins are one of the most important classes of heterocycles that occupies prime position in synthetic and pharmaceutical chemistry due to their diverse applications. Broad spectrum of biological activity and their utility as useful synthons, coumarins have attracted researchers to work on this moiety, which is instrumental in the development of coumarin chemistry. This review article provid...

Mosquitoes are the major vectors of parasites and pathogens affecting humans and domestic animals. The widespread development of insecticide resistance and negative environmental effects of most synthetic compounds support an interest in finding and developing alternative products against mosquitoes. Natural coumarins and synthetic coumarin analogues are known for their several pharmacological ...

Background: Coumarins and their derivatives excel in chemical diversity, coupled with a wide variety of biological potentials, tend to be beneficial the health human body. One these that has sparked attention medicinal chemistry specialists recent decades is benzo-fused coumarins, which have demonstrated potential as antioxidants, antimicrobials, antidiabetics, antithrombotics, many more. Objec...

In this review, we will present the different aspects of coumarins and derivatives, from natural origins or synthetically prepared, and their action on inflammation. Coumarins and also furo- and pyranocoumarins are found in many different plants. These compounds are very often investigated for antioxidant properties. Other biological properties are also possible and anti-inflammation activity i...

BACKGROUND The Australian cushion bush (Leucophyta brownii) of the Compositae family of plants has become a popular pot and container plant. The plant produces the sesquiterpene lactone allergen calocephalin. OBJECTIVES To assess the sensitizing potential of sesquiterpene lactones from cushion bush. PATIENTS/MATERIALS/METHODS Eleven Compositae-sensitive patients were patch tested with seven...