PubMed Health⌕ Search

PubMed · 16604744

Phytotherapy: rarely mentioned spontaneously.

Abstract

(1) In a German study, very few patients informed their healthcare providers that they were taking St John's wort. (2) St John's wort is an enzyme inducer and can therefore accelerate the elimination of many drugs, including vitamin K antagonists, hormonal contraceptives and immunosuppressants. This leads to a potential loss of efficacy of these drugs when taken in combination with St John's wort. On the other hand, there may be a risk of overdose when St John's wort is withdrawn. (3) In practice, patients must be carefully questioned about all treatments they are taking, including herbal products they do not consider worth mentioning.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

2006. Phytotherapy: rarely mentioned spontaneously.. https://pubmed.ncbi.nlm.nih.gov/16604744/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Addition of difluorocarbene to 3',4'-unsaturated nucleosides: synthesis of 2'-deoxy analogues with a 2-oxabicyclo[3.1.0]hexane framework.

Treatment of protected 2'-deoxy-3',4'-unsaturated nucleosides derived from adenosine and uridine with difluorocarbene [generated from bis(trifluoromethyl)mercury and sodium iodide] gave fused-ring 2,2-difluorocyclopropane compounds. Stereoselective alpha-face addition to the dihydrofuran ring resulted from hindrance by the protected beta-anomeric nucleobases. A protected uracil compound was converted smoothly into the cytosine derivative via a 4-(1,2,4-triazol-1-yl) intermediate. Removal of the protecting groups gave new difluorocyclopropane-fused nucleoside analogues. The solid-state conformation of the nearly planar furanosyl ring in the uracil compound had a shallow 2E pucker, and a more pronounced 1E conformation was present in the furanosyl ring of the cytosine derivative.

Bridged Bicyclo Compounds↗

Synthesis and structure-activity relationships of uracil nucleotide derivatives and analogues as agonists at human P2Y2, P2Y4, and P2Y6 receptors.

A series of UTP, UDP, and UMP derivatives and analogues were synthesized and evaluated at the human pyrimidinergic P2Y receptor subtypes P2Y2, P2Y4, and P2Y6 stably expressed in 1321N1 astrocytoma cells. Substituents at N3 of UTP were poorly tolerated by P2Y2 and P2Y4 receptors. In contrast, a large phenacyl substituent at N3 of UDP was well tolerated by the P2Y6 receptor, yielding a potent and selective P2Y6 receptor agonist (3-phenacyl-UDP, EC50=70 nM, >500-fold selective). The most potent and selective P2Y2 receptor agonist of the present series was 2-thio-UTP (EC50=50 nM, >or=30-fold selective vs P2Y4 and P2Y6). All modifications at the uracil base of UTP led to a decrease in potency at the P2Y4 receptor. A beta,gamma-dichloromethylene modification in the triphosphate chain of 5-bromo-UTP was tolerated by all three receptor subtypes, thus opening up a new strategy to obtain ectonucleotide diphosphohydrolase- and phosphatase-resistant P2Y2, P2Y4, and P2Y6 receptor agonists.

Bridged Bicyclo Compounds↗