Procedimiento para la preparación de merosesquiterpenos mediante cicloadición de Diels Alder de dienos derivados de diterpenos

Número de publicación: ES2563602 B1. Número de solicitud: 201400746.Universidad de GranadaUniversité Abdelmalek Essaâd

Chemical profile and in vitro antibacterial potential of essential oils and hydrolat extracts from aerial parts of three wild species of Moroccan Thymus

The present study aims to determine and compare the chemical composition of essential oils (EO) and hydrolat extracts (HE), isolated from three wild varieties of Moroccan thyme (T. satureioides Coss., T. willdenowii Boiss. and T. zygis L.) and to assess their antibacterial activity against four bacterial strains: Gram- (E. coli, Pr. Mirabilis) and Gram+ (B. subtilis, S. aureus). The findings showed that carvacrol (44.95%) and its biogenetic precursor p-cymene (23.36%) were the most dominant compounds of T. zygis L EO. The major volatile compounds in T. willdenowii Boiss EO were found to be thymol (42.38%), carvacrol (16.49%), and p-cymene (13.29%). Thus, T. satureioides Coss EO consists mainly of carvacrol (27.57%) and borneol (21.56%). On the other hand, carvacrol (72.33%) and thymol (10.70%) were the most prominent constituents in T. zygis L HE. T. willdenowii Boiss was dominated by thymol (65.01%) and carvacrol (21.74%). Furthermore, T. satureioides Coss HE was characterized by a high percentage of carvacrol (47.45%), borneol (25.04%), and γ-terpineol (19.34%). All investigated extracts exercised a strong antibacterial power against both tested Gram-positive and Gram-negative strains. However, the weakest activity was observed with T. satureioides Coss. EO and HE. The biological potential of HEs was found much higher than that of the corresponding EOs, which may give hydrolats a great value in aromatherapy to the detriment of essential oils

Diastereoselective Intramolecular Heck Reaction Assisted by an Acetate Group: Synthesis of the Decahydrobenzofluorene Derivative Dasyscyphin E

The first synthesis of antifungal sesquiterpene quinol dasyscyphin E was achieved starting from trans-communic acid. The process described involves the first diastereoselective synthesis of this type of compound by cyclization of an aryl bicyclosesquiterpene. The acid was efficiently transformed into a sesquiterpene synthon, which was converted into the corresponding bromoaryl sesquiterpene. The key step of synthetic sequence was the cyclization of the latter under Heck reaction conditions, which yielded the tetracyclic skeleton of the target compound with complete diastereoselectivity. The participation of an acetate group is decisive, both for the course of the Heck reaction and for the stereoselectivity of the process

Diastereoselective Intramolecular Heck Reaction Assisted by an Acetate Group: Synthesis of the Decahydrobenzofluorene Derivative Dasyscyphin E

The first synthesis of antifungal sesquiterpene quinol dasyscyphin E was achieved starting from <i>trans</i>-communic acid. The process described involves the first diastereoselective synthesis of this type of compound by cyclization of an aryl bicyclosesquiterpene. The acid was efficiently transformed into a sesquiterpene synthon, which was converted into the corresponding bromoaryl sesquiterpene. The key step of synthetic sequence was the cyclization of the latter under Heck reaction conditions, which yielded the tetracyclic skeleton of the target compound with complete diastereoselectivity. The participation of an acetate group is decisive, both for the course of the Heck reaction and for the stereoselectivity of the process

Diastereoselective Intramolecular Heck Reaction Assisted by an Acetate Group: Synthesis of the Decahydrobenzofluorene Derivative Dasyscyphin E

The first synthesis of antifungal sesquiterpene quinol dasyscyphin E was achieved starting from <i>trans</i>-communic acid. The process described involves the first diastereoselective synthesis of this type of compound by cyclization of an aryl bicyclosesquiterpene. The acid was efficiently transformed into a sesquiterpene synthon, which was converted into the corresponding bromoaryl sesquiterpene. The key step of synthetic sequence was the cyclization of the latter under Heck reaction conditions, which yielded the tetracyclic skeleton of the target compound with complete diastereoselectivity. The participation of an acetate group is decisive, both for the course of the Heck reaction and for the stereoselectivity of the process

First Enantiospecific Syntheses of Marine Merosesquiterpenes Neopetrosiquinones A and B: Evaluation of Biological Activity

The first enantiospecific syntheses of neopetrosiquinones A (<b>6</b>) and B (<b>7</b>), two merosesquiterpenes isolated from the deep-water sponge <i>Neopetrosia</i> cf. <i>proxima</i>, from the labdane diterpene <i>trans</i>-communic acid (<b>10</b>) have been achieved. A key step of the synthetic sequence is the simultaneous aromatization of the C ring and the benzylic oxidation on C-7 of an advanced intermediate, mediated by the oxygen–DDQ system. The in vitro antiproliferative activities of neopetrosiquinone B (<b>7</b>) and of the synthetic intermediates <b>8</b> and <b>9</b> against human breast (MCF-7), lung (A-549), and colon (T-84) tumor cell lines have been assayed. The most potent was compound <b>9</b> (IC₅₀ = 4.1 μM), which was twice as active as natural compound <b>7</b> (IC₅₀ = 8.3 μM) against A-549 cells. In addition, the treatment with these compounds resulted in an induction of apoptosis. These findings indicate that the terpene benzoquinones reported here might be potentially useful as anticancer agents