119 research outputs found
Synthesis and Biological Evaluation of 3,16,20-Polyoxygenated Steroids of Marine Origin and Their Analogs
ABSTRACT The natural polyoxygenated steroids (20S)-20-hydroxycholestane-3,16-dione (1), (16S, 20S)-16,20-dihydroxycholestan-3-one (2), (20S)-20-hydroxycholest-1-ene-3,16-dione (3) and (20S)-20-hydroxycholest-4-ene-3,16-dione (4), isolated from the gorgonian, Leptogorgia sarmentosa and unnatural analogs (5) (6)
Glycozolidal
The title compound known as glycozolidal (systematic name: 2,7-dimethoxy-9H-carbazole-3-carbaldehyde), C15H13NO3, is a naturally occurring carbazole, which was isolated from the roots of Clausena lansium. The carbazole ring system is essentially planar, with an r.m.s. deviation of 0.0093 (1) Å. In the crystal, intermolecular N—H⋯O hydrogen bonds connect the molecules into a chain along the c axis. C—H⋯O, C—H⋯π and π–π interactions, with centroid–centroid distances of 3.5924 (6), 3.6576 (6) and 3.8613 (6) Å, are also observed
A Facile Palladium Catalysed 3-Component Cascade Route to Functionalised Isoquinolinones and Isoquinolines
Palladium catalysed three component cascade process, involving coupling of 2-iodobenzoates, -benzaldehydes, or acetophenones with substituted allenes and ammonium tartrate as an ammonium surrogate, provides a novel and facile route to substituted functionalised isoquinolinones and isoquinolines in good yields
2-Hydroxy-7-methoxy-9H-carbazole-3-carbaldehyde
The title compound, C14H11NO3, was isolated from the roots of Clausena wallichii. The carbazole ring system is approximately planar (r.m.s. deviation = 0.039 Å) and the dihedral angle between the two benzene rings is 4.63 (7)°. An intramolecular O—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked into a zigzag network extending parallel to the ac plane by O—H⋯N and N—H⋯O hydrogen bonds
Evaluation of the anti-inflammatory effects of synthesised tanshinone I and isotanshinone I analogues in zebrafish
During inflammation, dysregulated neutrophil behaviour can play a major role in a range of chronic inflammatory diseases, for many of which current treatments are generally ineffective. Recently, specific naturally occurring tanshinones have shown promising anti-inflammatory effects by targeting neutrophils in vivo, yet such tanshinones, and moreover, their isomeric isotanshinone counterparts, are still a largely underexplored class of compounds, both in terms of synthesis and biological effects. To explore the anti-inflammatory effects of isotanshinones, and the tanshinones more generally, a series of substituted tanshinone and isotanshinone analogues was synthesised, alongside other structurally similar molecules. Evaluation of these using a transgenic zebrafish model of neutrophilic inflammation revealed differential anti-inflammatory profiles in vivo, with a number of compounds exhibiting promising effects. Several compounds reduce initial neutrophil recruitment and/or promote resolution of neutrophilic inflammation, of which two also result in increased apoptosis of human neutrophils. In particular, the methoxy-substituted tanshinone 39 specifically accelerates resolution of inflammation without affecting the recruitment of neutrophils to inflammatory sites, making this a particularly attractive candidate for potential pro-resolution therapeutics, as well as a possible lead for future development of functionalised tanshinones as molecular tools and/or chemical probes. The structurally related β-lapachones promote neutrophil recruitment but do not affect resolution. We also observed notable differences in toxicity profiles between compound classes. Overall, we provide new insights into the in vivo anti-inflammatory activities of several novel tanshinones, isotanshinones, and structurally related compounds
ChemInform Abstract: SHORT-STEP SYNTHESIS OF 1,3-DIMETHYL-2,9-DIOXABICYCLO(3.3.1)NONANE: AN INSECT ATTRACTANT
New Strategy for Synthesis of the Disaccharide Moiety of the Highly Potent Anticancer Natural Product OSW-1
<div><p></p><p>The facile synthesis of a partially protected OSW-1 disaccharide moiety, having a 2-O-p-methoxybenzoyl-β-D-xylopyranosyl-(1 → 3)-2-O-acetyl-L-arabinopyranoside structure, was elaborated by glycosylation in a β-stereoselective fashion. The xylopyranose donors were synthesized by a short synthetic approach via convenient selective 1,2-diacetal protection of 3,4-<i>trans</i>-diequatorial hydroxyl group. Regioselective ring opening of 1,2-diacetal-protected substrates efficiently led to the arabinopyranose acceptor with a free 3-hydroxyl group. Glycosylation of the xylopyranose donor with the arabinopyranose acceptor provided the β-disaccharide.</p>
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ChemInform Abstract: Syntheses of Both Diastereoisomers of 2,8-Dioxabicyclo[3.2.1]octane Derivatives: Degradation Products of Daphniphyllum Alkaloids.
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