30 research outputs found
9-O-Ethylberberrubinium iodide monohydrate
In the title compound (systematic name: 9-ethoxy-10-methoxy-5,6-dihydro-1,3-dioxolo[4,5-g]isoquinolino[3,2-a]isoquinolin-7-ium iodide monohydrate), 2C21H20NO4
+·2I−·H2O, two independent molecules pack in the unit cell, where interactions between the molecules are stabilized by weak intermolecular π–π stacking interactions [centroid–centroid distances in the range 3.571 (4) to 3.815 (4)Å]. Intermolecular C—H⋯O interactions are also observed. The iodide anions are disordered with occupancy ratios of 0.94 (1):0.06 (1) and 0.91 (1):0.09 (1). The cationic molecule is planar in structure with a small torsion resulting from the dihydropyridine ring
7,9-Dichloro-6H,12H-indolo[2,1-b]quinazoline-6,12-dione
There are two independent molecules in the asymmetric unit of the title compound, C15H6Cl2N2O2. The conjugated four-ring system is essentially planar in each molecule [maximum deviation = 0.089 (2) Å]. In the crystal, weak intermolecular C—H⋯Cl, C—H⋯O and C—H⋯·N interactions help to stabilize the packing
Activated plasma coagulation β-Factor XII-induced vasoconstriction in rats
By inducing BK (bradykinin)-stimulated adrenomedullary catecholamine release, bolus injection of the β-fragment of activated plasma coagulation Factor XII (β-FXIIa) transiently elevates BP (blood pressure) and HR (heart rate) of anaesthetized, vagotomized, ganglion-blocked, captopril-treated bioassay rats. We hypothesized that intravenous infusion of β-FXIIa into intact untreated rats would elicit a qualitatively similar vasoconstrictor response. BN (Brown Norway) rats received for 60 min either: (i) saline (control; n=10); (ii) β-FXIIa (85 ng/min per kg of body weight; n=9); or (iii) β-FXIIa after 2ADX (bilateral adrenalectomy; n=9). LV (left ventricular) volume and aortic BP were recorded before (30 min baseline), during (60 min) and after (30 min recovery) the infusion. TPR (total peripheral resistance) was derived from MAP (mean arterial pressure), SV (stroke volume) and HR. Saline had no haemodynamic effects. β-FXIIa infusion increased its plasma concentration 3-fold in both groups. In adrenally intact rats, β-FXIIa infusion increased MAP by 6% (5±2 mmHg) and TPR by 45% (0.50±0.12 mmHg/ml per min), despite falls in SV (−38±8 μl) and HR [−18±5 b.p.m. (beats/min)] (all P<0.05). In 2ADX rats, β-FXIIa had no HR effect, but decreased SV (−89±9 μl) and MAP (−4±1 mmHg), and increased TPR by 66% (0.59±0.15 mmHg/ml per min) (all P<0.05). After infusion, adrenally intact rats exhibited persistent vasoconstriction (MAP, 10±1 mmHg; TPR, 0.55±0.07 mmHg/ml per min; both P<0.05), whereas in 2ADX rats, MAP remained 5±1 mmHg below baseline (P<0.05) and TPR returned to baseline. End-study arterial adrenaline (epinephrine) concentrations in the three groups were 1.9±0.6, 9.8±4.1 and 0.6±0.2 nmol/l respectively. Thus, in neurally intact lightly anaesthetized untreated rats, β-FXIIa infusion induces both adrenal catecholamine-mediated and adrenally independent increases in peripheral resistance
Heck reaction and carbonyl reactions - a versatile combination
Die Heck-Reaktion von ungesättigten Alkoholen führt zu Aldehyden oder Ketonen. Diese Art von Heck-Reaktion kann bei Einsatz von ungesättigten Carbonylverbindungen als aromatische Kupplungskomponenten mit klassischen Carbonylreaktionen wie einer Robinson-analogen Anellierung kombiniert werden. Die intermolekulare Version dieses Domino-Prozesses ist ein Zugang zu Phenanthrensystemen. Durch eine intramolekulare Heck-Reaktion als makrozyklisierende Ringschlußreaktion gefolgt von einer Sequenz aus einer Michael- Reaktion und einer Aldol-Kondensation wird ein Steroidgerüst erhalten. Aus einfachen Ausgangsmaterialen ist somit eine breite Produktpalette von komplexen Zielmolekülen zugänglich.
The Heck reaction with unsaturated alcohols yields aldehydes or ketones. Employing unsaturated carbonyl compounds as coupling components this type of Heck reaction can be combined with classical carbonyl reactions such as a Robinson-type annulation: The intermolecular version of this domino process is an access to phenanthrene systems. Using an intramolecular Heck reaction as a macrocyclic ring closure reaction followed by sequence consisting of a Michael addition and an Aldol condensation a steroid skeleton is obtained. Hence, a wide range of complex target molecules is accessible from simple building blocks
Inhibition of Toxoplasma gondii by Indirubin and Tryptanthrin Analogs ▿
New drugs are needed for treatment of Toxoplasma gondii infections. We tested derivatives of principles found in Isatis indigotica for in vitro efficacy against T. gondii infection. Indirubin-3′-oxime analogs showed modest micromolar activity, while tryptanthrin derivatives displayed 50% inhibitory doses in the low nanomolar range. Tryptanthrins have potential as anti-Toxoplasma infection therapeutics
rac-(6S)-6-Hydroxy-6-{2-[2-(propan-2-ylidene)hydrazinylidene]propyl}indolo[2,1-b]quinazolin-12(6H)-one
The chiral title compound, C21H20N4O2, crystallizes as a racemic mixture. In the crystal, molecules form centrosymmetric &#960;-overlapping dimers [interplanar distance = 3.338&#8197;(6)&#8197;&#197;], which are further connected along the a axis forming centrosymmetric dimers via O&#8212;H...N hydrogen bonds. C&#8212;H...O interactions are also observed. The indolo[2,1-b]quinazoline group is somewhat bent, with a small dihedral angle of 6.3&#8197;(4)&#176; between the plane of the quinazoline system and the plane of the benzene ring of the indole moiety. The C=N&#8212;N=C atoms of the azine group is oriented almost perpendicular [84.1&#8197;(2)&#176;] to the mean plane of the quinazoline system