Two robust catechol-functionalized porous organic polymers (catPOPs) with different Td-directing nodes were synthesized using a cobalt-catalyzed acetylene trimerization (CCAT) strategy. Postsynthesis metallation was readily carried out with La(acac)3 to afford catalytically active Lafunctionalized catPOPs for the solvolytic and hydrolytic degradation of the toxic organophosphate compound methyl...

Salsolinol, 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline, is an endogenous catechol isoquinoline detected in humans by M. Sandler. In human brain, a series of catechol isoquinolines were identified as the condensation products of dopamine or other monoamines with aldehydes or keto-acids. Recently selective occurrence of the (R)enantiomers of salsolinol derivatives was confirmed in huma...

Tetrahydroprotoberberine and protoberberine alkaloids are a group of biologically active natural products with complex molecular scaffolds. Isolation from plants is challenging stereoselective synthetic routes, particularly methylated compounds limited, reducing the potential use these compounds. In this work, we describe chemoenzymatic cascades toward various 13-methyl-tetrahydroprotoberberbin...

A novel isoquinolinone alkaloid, iseluxine (1), has been isolated from the epigeal parts of Iseia luxurians (MORIC.) O'DONELL (Convolvulaceae), a climber indigenous to the tropical Americas. Structural elucidation was achieved by HRMS, 1H NMR, 13C NMR, and HMBC spectroscopy. N- and/or O-methyl derivatives of 1 are already known from certain Magnoliidae families, e.g., the Fumariaceae, the Laura...

The involvement of estrogens in carcinogenic processes within estrogen-responsive tissues has been recognized for a number of years. Classically, mitogenicity associated with estrogen receptor-mediated cellular events was believed to be the mechanism by which estrogens contributed to carcinogenesis. Recently, the possibility that estrogens might contribute directly to mutagenesis resulting from...

DFT calculations for methyl cation complexed within a constrained cage of water molecules permit the controlled manipulation of the "axial" donor/acceptor distance and the "equatorial" distance to hydrogen-bond acceptors. The kinetic isotope effect k(CH3)/k(CT3) for methyl transfer within a cage with a short axial distance becomes less inverse for shorter equatorial C⋅⋅⋅O distances: a decrease ...

Tyrosinase shows kinetic cooperativity in its action on o-diphenols, but not when it acts on monophenols, confirming that the slow step is the hydroxylation of monophenols to o-diphenols. This model can be generalised to a wide range of substrates; for example, type S(A) substrates, which give rise to a stable product as the o-quinone evolves by means of a first or pseudo first order reaction (...

Exposure to polycyclic aromatic hydrocarbons (PAHs) in the food chain is the major human health hazard associated with the Deepwater Horizon oil spill. Phenanthrene is a representative PAH present in crude oil, and it undergoes biological transformation, photooxidation, and chemical oxidation to produce its signature oxygenated derivative, phenanthrene-9,10-quinone. We report the downstream met...

IN THE PRESENT WORK, SEVERAL FATTY ACID METHYL ESTERS (FAME) HAVE BEEN SYNTHESIZED FROM VARIOUS FATTY ACID FEEDSTOCKS: used frying olive oil, pork fat, soybean, rapeseed, sunflower, and coconut. The oxidation stabilities of the biodiesel samples and of several blends have been measured simultaneously by both the Rancimat method, accepted by EN14112 standard, and the PetroOXY method, prEN16091 s...