ABSTRACT
The biosynthesis of the meroterpenoid guajadial was previously hypothesized to occur via a hetero-Diels-Alder reaction between caryophyllene and an o-quinone methide. This hypothesis has been verified via the biomimetic synthesis of guajadial and psidial A in an aqueous three-component coupling reaction, between caryophyllene, benzaldehyde, and diformylphloroglucinol.
Subject(s)
Biomimetics , Sesquiterpenes/chemical synthesis , Terpenes/chemical synthesis , Models, Molecular , Molecular Conformation , Sesquiterpenes/chemistry , Terpenes/chemistryABSTRACT
The partial reduction of electron deficient pyrroles is an extremely versatile method that allows us to prepare substituted pyrrolidines and pyrrolizidines with trans-diol stereochemistry on the five membered ring.
Subject(s)
Pyrrolizidine Alkaloids/chemical synthesis , Sorbitol/analogs & derivatives , Pyrroles/chemistry , Pyrrolizidine Alkaloids/chemistry , Sorbitol/chemical synthesis , Sorbitol/chemistry , StereoisomerismABSTRACT
The effect of Cu(II) on the determination of homocysteine via its electrochemically initiated reaction with N, N-diethyl-p-phenylenediamine is examined. The presence of copper inhibited the detection process for homocysteine owing to a complexation reaction occurring. This provided an indirect route for the sensitive and selective determination of Cu(II), which produced a linear response over the range from 2.5 to 500 microM and a limit of detection of 2.5 microM. The detection pathway was examined in the presence of metallic and inorganic ions, with negligible interference observed.
