RESUMO
We present a case of a 31-year-old patient, smoker, with no previous medical history, presenting with acute limb ischemia and infarction of the spleen due to peripheral embolism. The source of embolism was thrombi formations in the left ventricular cavity, located in the area of the regional wall motions abnormalities. CT and coronary angiography confirmed the total occlusion of the left anterior descending artery with collateralization. The patient underwent acute bilateral embolectomy of the iliac, femoral, and popliteal arteries. Subsequently, cardiothoracic surgery was indicated with coronary bypass surgery and extirpation of left ventricular masses, later confirmed as thrombus by pathology characteristics. Hematological examinations proved homozygous thrombophilia, and the patient was indicated for lifelong anticoagulation therapy.
RESUMO
Dihydrofuro[2,3-f]indolizidinone obtained from biosourced reagents even at multigram-scale was used as an advanced building-block with up to five points of chemical diversification. This resulted in the sequential synthesis of a series of mono-, di- and tetra-hydroxyfuranoindolizidines belonging to a very scarce and elaborate tetrahydrofuran-fused indolizidine family with up to six controlled stereogenic centers. These sequences include, among others, diastereoselective olefin epoxidation, stereoselective epoxide ring opening into tetrahydrofuran trans-diols, their protection as an ester or acetonide, and lactam carbonyl reduction ultimately followed by acetate or acetonide deprotection.
RESUMO
We describe the screening of a set of cryptopleurine derivatives, namely thienoquinolizidine derivatives and (epi-)benzo analogs with bioactive phenanthroquinolizidine alkaloids that induce cytotoxic effects in the mouse lymphocytic leukemia cell line L1210. We used three variants of L1210 cells: i) parental cells (S) negative for P-glycoprotein (P-gp) expression; ii) P-glycoprotein positive cells (R), obtained by selection with vincristine; iii) P-glycoprotein positive cells (T), obtained by stable transfection with a human gene encoding P-glycoprotein. We identified the most effective derivative 11 with a median lethal concentration of ≈13 µM in all three L1210 cell variants. The analysis of the apoptosis/necrosis induced by derivative 11 revealed that cell death was the result of apoptosis with late apoptosis characteristics. Derivative 11 did not induce a strong alteration in the proportion of cells in the G1, S or G2/M phase of the cell cycle, but a strong increase in the number of S, R and T cells in the subG1 phase was detected. These findings indicated that we identified the most effective inducer of cell death, derivative 11, and this derivative effectively induced cell death in S, R and T cells at similar inhibitory concentrations independent of P-gp expression.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Leucemia/metabolismo , Leucemia/patologia , Fenantrolinas/análise , Fenantrolinas/farmacologia , Quinolizinas/análise , Quinolizinas/farmacologia , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Concentração Inibidora 50 , Modelos Moleculares , Fenantrolinas/química , Quinolizinas/química , Coloração e Rotulagem , Proteína X Associada a bcl-2/metabolismoRESUMO
Pt(II)-catalyzed carbocyclization of benzaldehyde containing a keto-nitrile functionality resulted in the formation, respectively, of isochromenes and spiro-lactones instead of fused lactams and spiro-lactams as was previously reported. The reaction mechanism was proposed, and the products were identified by multidimensional NMR, IR, and X-ray analysis. The structure of these new products was also confirmed by their synthesis in an unambiguous manner using practical and short approaches.
RESUMO
The stereoselective synthesis of epi-thieno analogues of the phenanthroquinolizidine bioactive alkaloids (-)-Cryptopleurine and (-)-(15R)-Hydroxycryptopleurine was achieved in five steps starting from easily available enantiopure (S)-2-aminoadipic acid used as chiral pool and nitrogen atom source. During these investigations, both π-cationic cyclization of chiral N-thienylmethyl-6-oxopipecolinic acids into pure (S)-keto-lactams and theirs regioselective and diastereoselective reduction, considered as key steps of this sequence, were studied. Of particular interest, the Friedel-Crafts cyclization using (CF3CO)2O/BF3·Et2O show that near the expected keto-lactams, enamides and enamidones containing trifluoromethyl residue were isolated. A mechanism leading to the latter products with high synthetic potential was discussed.
RESUMO
Molecules of (S)-6-oxo-1-(thiophen-2-ylmethyl)piperidine-2-carboxylic acid, C11H13NO3S, crystallize as single enantiomers in the space group P21 and the thiophene ring is disordered over two positions, while (S)-6-oxo-1-(thiophen-3-ylmethyl)piperidine-2-carboxylic acid, C11H13NO3S, crystallizes as a single enantiomer in the space group P212121. Their absolute configurations were confirmed by anomalous dispersion effects in diffraction measurements on the crystals. The molecules of each compound are linked by a combination of strong O-H...O hydrogen bonds and weak C-H...O interactions, resulting in two- and three-dimensional networks, respectively, in the crystal structures.
Assuntos
Ácidos Carboxílicos/química , Ácidos Pipecólicos/síntese química , Piperidinas/química , Tiofenos/química , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular , Ácidos Pipecólicos/químicaRESUMO
The absolute configuration of the title compound, C14H13NOS, was assigned from the synthesis and confirmed by the structure determination. There are two independent mol-ecules in the asymmetric unit. The central six-membered ring of the indolizine moiety adopts an envelope conformation, with the greatest deviations from the mean planes being 0.569â (3) and 0.561â (3)â Å for the indolizine bridgehead C atoms of the two mol-ecules. The benzothieno ring attached to the indolizine ring system is planar to within 0.015â (3)â Å in both mol-ecules. In the crystal, weak C-Hâ¯O and C-Hâ¯π inter-actions lead to the formation of a three-dimensional framework structure.
RESUMO
The title compound, C(10)H(11)NO(3), crystallizes with four independent mol-ecules in the asymmetric unit. Their geometries are very similar and corresponding bond distances are almost identical. The central six-membered ring of the indolizine moiety adopts a envelope conformation [the displacement of the flap atom (the C atom opposite the N atom) being 0.539â (2), 0.548â (3), 0.509â (3) and 0.544â (3)â Å in the four molecules], while the conformation of the oxopyrrolidine ring is close to that of a flat envelope. The displacements of the non-fused C atom opposite the C=O group of the pyrrolidine ring of the four mol-ecules are 0.366â (3), 0.335â (3), 0.173â (3) and -0.310â (3)â Å. In the crystal, O-Hâ¯O hydrogen bonds link the mol-ecules into chains, which run parallel to the c axis. The absolute configuration was assigned from the synthesis.
RESUMO
In the mol-ecular structure of the title compound, C(14)H(21)NO(5), the six-membered ring of the indolizine moiety adopts a chair conformation. There are two independent mol-ecules in the asymmetric unit. The oxopyrrolidine ring attached to the indolizine ring system is nearly planar, with mean deviations of 0.018â (3) and 0.010â (3)â Å for the two mol-ecules. The absolute configuration of the title compound was assigned from the synthesis.
RESUMO
The absolute configuration of the title compound, C14H13NO3S, was assigned from the synthesis and confirmed by the structure determination. The central six-membered ring of the indolizine moiety adopts an envelope conformation, with the greatest deviation from the mean plane of the ring being 0.661â (2)â Å for the bridgehead C atom. The benzothiene ring attached to the indolizine ring system is planar to within 0.008â (2)â Å. In the crystal, mol-ecules form chains parallel to the b axis via O-Hâ¯O hydrogen bonds.
RESUMO
The title compound, C(11)H(22)NO(2) (+)·I(-), is a chiral mol-ecule with five stereogenic centres. The absolute configuration was assigned from the synthesis and confirmed by the structure determination. The central six-membered ring of the indolizine system adopts a chair conformation, with two atoms displaced by -0.690â (2) and 0.550â (2)â Å from the plane of the other four atoms. The conformation of the pyrrolidine ring is close to that of an envelope, with the flap atom displaced by 0.563â (2)â Å from the plane of the remaining four atoms. In the crystal, there are two O-Hâ¯I hydrogen bonds.
RESUMO
The title compound, C(10)H(9)NO(3), is a chiral mol-ecule with one stereogenic carbon atom, but which crystallizes as a racemate in the centrosymmetric space group P2(1)/n. The central six-membered ring of the indolizine moiety adopts a definite envelope conformation, while the conformation of the oxopyrrolidine ring is close to that of a flat-envelope with a maximum deviation of 0.352â (1)â Å for the flap atom.
RESUMO
The absolute configuration of the title compound, C(10)H(17)NO(3)·H(2)O, was assigned from the synthesis. In the mol-ecular structure, the central six-membered ring of the indolizine moiety adopts a chair conformation, with two atoms displaced by -0.578â (2) and 0.651â (1)â Å from the plane of the other four atoms [maximum deviation 0.019â (2)â Å] The conformation of the fused oxopyrrolidine ring is close to that of a flat envelope, with the flap atom displaced by 0.294â (1)â Å from the plane through the remaining four atoms. In the crystal, one of the hy-droxy groups is hydrogen-bonded to two water mol-ecules, while the other hy-droxy group exhibits an inter-molecular hydrogen bond to the carbonyl O atom, resulting in a chain parallel to the b axis.
RESUMO
Prolonged standard cardiopulmonary resuscitation (CPR) does not reliably sustain brain viability during cardiac arrest. Pre-hospital adjuncts to standard CPR are needed in order to improve outcomes. A preliminary dog study demonstrated that surface cooling of the head during arrest and CPR can achieve protective levels of brain hypothermia (30°C) within 10 minutes. We hypothesized that protective head-cooling during cardiac arrest and CPR improves neurological outcomes. Twelve dogs under light ketamine-halothane-nitrous oxide anesthesia were arrested by transthoracic fibrillation. The treated group consisted of six dogs whose shaven heads were moistened with saline and packed in ice immediately after confirmation of ventricular fibrillation. Six control dogs remained at room temperature. All 12 dogs were subjected to four minutes of ventricular fibrillation and 20 minutes of standard CPR. Spontaneous circulation was restored with drugs and countershocks. Intensive care was provided for five hours post-arrest and the animals were observed for 24 hours. In both groups, five of the six dogs had spontaneous circulation restored. After three hours, mean neurological deficit was significantly lower in the treated group (P=0.016, with head-cooled dogs averaging 37% and the normothermic dogs 62%). Two of the six head-cooled dogs survived 24 hours with neurological deficits of 9% and 0%, respectively. None of the control group dogs survived 24 hours. We concluded that head-cooling attenuates brain injury during cardiac arrest with prolonged CPR. We review the literature related to the use of hypothermia following cardiac arrest and discuss some promising approaches for the pre-hospital setting.
RESUMO
In the mol-ecular structure of the title compound, C(10)H(11)NOS, the central six-membered ring of the indolizine unit adopts an envelope conformation, the maximum deviations from the mean plane of the ring being 0.533â (2)â Å. The fused thieno ring is nearly coplanar [mean deviation = 0.007â (2)â Å]. The conformation of the fused oxopyrrolidine ring is close to that of a flat-envelope, with a maximum deviation of 0.339â (3)â Å. The crystal structure is stabilized by C-Hâ¯O hydrogen bonds.
RESUMO
In the title compound, C(14)H(17)NO(2), the six-membered ring of the indolizine system adopts a chair conformation. In the crystal, mol-ecules form chains parallel to the b axis via inter-molecular O-Hâ¯O hydrogen bonds. The absolute mol-ecular configuration was assigned from the synthesis.
RESUMO
The absolute configuration of the title compound, C(14)H(13)NO(2)S, was assigned from the synthesis and confirmed by the structure determination. The central six-membered ring of the indolizine system adopts an envelope conformation, the greatest deviation from the mean plane of the ring being 0.459â (2)â Å for the N atom. The benzothieno system is planar [mean deviation = 0.009â (2)â Å]. In the crystal structure, mol-ecules form chains parallel to the b axis via inter-molecular O-Hâ¯O hydrogen bonds.
RESUMO
BACKGROUND: In a previous study, titration of a hypertonic saline (HTS) solution during severe uncontrolled hemorrhagic shock (UHS) failed to reduce mortality. In a separate study, a novel antioxidant, polynitroxylated albumin (PNA) plus tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl), infused during shock increased long-term survival. We hypothesized that combining potent antioxidants with a hypertonic solution during UHS would preserve the logistical advantage of small volume resuscitation and improve survival. METHODS: An UHS outcome model in rats was used. UHS phase I (90 min) included blood withdrawal of 30 ml/kg over 15 min, followed by tail amputation for uncontrolled bleeding. At 20 min, rats were randomized to four groups (n=10 each) for hypotensive resuscitation from 20 to 90 min (mean arterial pressure [MAP] > or = 40 mmHg): HTS/starch group received 7.2% NaCl/10% hydroxyethyl starch; HTS/albumin group received 7.5% NaCl/20% albumin; HTS/PNA group received 7.5% NaCl/20% PNA; HTS/albumin+tempol group received 7.5% NaCl/20% albumin plus tempol. Resuscitation phase II (180 min) included hemostasis, return of shed blood and administration of fluids to restore MAP > or = 80 mmHg. Observation phase III was to 72 h. RESULTS: The total amount of fluid required to maintain hypotensive MAP during HS was low and did not differ between groups (range: 3.4+/-1.9 to 5.3+/-2.5 ml/kg). The rate of fluid administration required was higher in the HTS/albumin+tempol group compared to all other groups (p=0.006). Additional uncontrolled blood loss was highest in the HTS/PNA group (16.2+/-5.7 ml/kg [p=0.01] versus 10.4+/-7.9 ml/kg in the HTS/starch group, 7.7+/-5.2 ml/kg in the HTS/albumin group and 8.2+/-7.1 ml/kg in the HTS/albumin+tempol group). MAP after start of resuscitation in phase I was lower in the HTS/albumin+tempol group than the HTS/albumin or HTS/PNA groups (p<0.01). This group was also less tachycardic. Long-term survival was low in all groups (2 of 10 after HTS/starch and 1 of 10 after HTS/albumin, 3 of 10 after HTS/PNA, 1 of 10 after HTS/albumin+tempol). Median survival time was shortest in the HTS/albumin+tempol group (72 min [CI 34-190]) compared to all other groups (p=0.01). CONCLUSIONS: Despite its benefits in other model systems, free tempol is potentially hazardous when combined with hypertonic fluids. PNA abrogates these deleterious effects on acute mortality but may lead to increased blood loss in the setting of UHS.
Assuntos
Albuminas/farmacologia , Antioxidantes/efeitos adversos , Óxidos N-Cíclicos/efeitos adversos , Ressuscitação , Solução Salina Hipertônica/administração & dosagem , Choque Hemorrágico/terapia , Animais , Antioxidantes/farmacologia , Óxidos N-Cíclicos/farmacologia , Modelos Animais de Doenças , Sinergismo Farmacológico , Hidratação/métodos , Hematócrito , Masculino , Ratos , Ratos Sprague-Dawley , Ressuscitação/métodos , Choque Hemorrágico/mortalidade , Choque Hemorrágico/fisiopatologia , Marcadores de Spin , Taxa de SobrevidaRESUMO
BACKGROUND: Mild hypothermia improves outcome when induced after cardiac arrest in humans. Recent studies in both dogs and mice suggest that induction of mild hypothermia during cardiopulmonary resuscitation (CPR) greatly enhances its efficacy. In this study, we evaluate the time window for the beneficial effect of intra-arrest cooling in the setting of prolonged CPR in a clinically relevant large-animal model. METHODS AND RESULTS: Seventeen dogs had ventricular fibrillation cardiac arrest no flow of 3 minutes, followed by 7 minutes of CPR basic life support and 50 minutes of advanced life support. In the early hypothermia group (n=9), mild hypothermia (34 degrees C) was induced with an intravenous fluid bolus flush and venovenous blood shunt cooling after 10 minutes of ventricular fibrillation. In the delayed hypothermia group (n=8), hypothermia was induced at ventricular fibrillation 20 minutes. After 60 minutes of ventricular fibrillation, restoration of spontaneous circulation was achieved with cardiopulmonary bypass for 4 hours, and intensive care was given for 96 hours. In the early hypothermia group, 7 of 9 dogs survived to 96 hours, 5 with good neurological outcome. In contrast, 7 of 8 dogs in the delayed hypothermia group died within 37 hours with multiple organ failure (P=0.012). CONCLUSIONS: Early application of mild hypothermia with cold saline during prolonged CPR enables intact survival. Delay in the induction of mild hypothermia in this setting markedly reduces its efficacy. Our data suggest that if mild hypothermia is used during CPR, it should be applied as early as possible.