Regioselective synthesis and biological evaluation of N-substituted 2-aminoquinazolin-4-ones.

The reaction of methyl anthranilates with N-arylcyanamides in the presence of p-TsOH in t-BuOH under reflux afforded predominantly 3-arylquinazolin-4-ones. In contrast, the reaction of the same reactants with TMSCl in t-BuOH at 60 °C followed by the Dimroth rearrangement in aqueous ethanolic sodium hydroxide gave exclusively the regioisomers, 2-(N-arylamino)quinazolin-4-ones. The regioselective synthesis of N-aryl-substituted 2-aminoquinazolin-4-ones can be further applied to the synthesis of benzimidazo[2,1-b]quinazolin-12-ones.

CuI-Catalyzed intramolecular aminocyanation of terminal alkynes in N-(2-ethynylphenyl)-N-sulfonylcyanamides via Cu-vinylidene intermediates.

CuI-Catalyzed intramolecular aminocyanation of terminal alkynes in N-(2-ethynylphenyl)-N-sulfonylcyanamides was initiated by the formation of Cu-acetylide to trigger N-CN bond cleavage of the N-sulfonylcyanamide moiety followed by CN migration to form a ß-cyano Cu-vinylidene intermediate. Subsequently, the indole ring closure furnished the corresponding 1-sulfonyl-3-cyanoindoles.

Teenager with chest pain and swollen neck: a leave-it-alone condition.

A 19-year-old boy with shortness of breath and chest pain after strenuous exercise presented to emergency department . On physical examination, the neck and shoulders appeared to be swollen. There was crepitus on skin palpation. Chest X-ray disclosed diffuse subcutaneous emphysema and pneumomediastinum. CT showed additional finding of air in epidural space. The patient was discharged after 2 days of hospitalisation with conservative treatment uneventfully. Pneumorrhachis is usually caused by abrupt increase in intrathoracic pressure in instance of forceful vomiting, cough or asthma attack in an otherwise healthy young adult. It is usually accompanied with pneumomediastinum. The management of epidural pneumatosis should be tailored according to its primary cause. For most patients with pneumorrhachis associated to a spontaneous pneumomediastinum without neurological symptoms, this condition is generally self-limited. For epidural free air of large volume that causes neurological deficits, surgical laminectomy may be indicated.

Hypertensive brain stem encephalopathy.

A 48-year-old man presented with headache and extreme hypertension. Computed tomography showed diffuse brain stem hypodensity. Magnetic resonance imaging revealed diffuse brain stem vasogenic edema. Hypertensive brain stem encephalopathy is an uncommon manifestation of hypertensive encephalopathy, which classically occurs at parietooccipital white matter. Because of its atypical location, the diagnosis can be challenging. Moreover, the coexistence of hypertension and brain stem edema could also direct clinicians toward a diagnosis of ischemic infarction, leading to a completely contradictory treatment goal.

Practical synthesis of N-substituted cyanamides via Tiemann rearrangement of amidoximes.

A facile and general synthesis of various N-substituted cyanamides was accomplished by the Tiemann rearrangement of amidoximes with benzenesulfonyl chlorides (TsCl or o-NsCl) and DIPEA.

Acid-base interpretation can be the predictor of outcome among patients with acute organophosphate poisoning before hospitalization.

OBJECTIVES: Acute organophosphate (OP) poisoning causing alteration in acid-base equilibrium was reported before. Hence, different acid-base statuses may present in patients with acute poisoning due to OP exposure. This study aims to determine the impact of acid-base interpretation in patients with acute OP poisoning before hospitalization in medical care units and to describe the pattern of mortality with different acid-base statuses. DESIGN AND PATIENTS: Over a 9-year retrospective study, from July 1996 to August 2005, a total of 82 consecutive patients with acute OP poisoning were admitted to the China Medical University Hospital (Taichung, Taiwan) within 24 hours after exposure to OP and were enrolled into this study. RESULTS: Patients with acute OP poisoning were divided into 4 groups: without acidosis, metabolic acidosis, respiratory acidosis, and mixed acidosis. Overall survival (Kaplan-Meier curves) among groups was statistically significant (P < .0001). The mortality rate of acute OP poisoned patients with metabolic acidosis was 25%, and 75% of those patients died of cardiovascular failure. The mortality rate of acute OP poisoning with respiratory acidosis was 50%, and 50% of those patients died of respiratory failure. CONCLUSIONS: Acid-base interpretation can be effective in quick diagnosis and prediction of the outcome of patients with acute OP poisoning (without acidosis < metabolic acidosis < respiratory acidosis < mixed acidosis) before hospitalization. Major causes of death are different between the respiratory acidosis and metabolic acidosis groups of patients with acute OP poisoning.

A comparison of sevelamer hydrochloride with calcium acetate on biomarkers of bone turnover in hemodialysis patients.

OBJECTIVE: To evaluate the influence of sevelamer hydrochloride and calcium acetate on biomarkers of bone turnover in patients with hyperphosphatemia receiving hemodialysis. METHODS: In this prospective, open-label, randomized, active-controlled study, 70 patients (38 men and 32 women) with hyperphosphatemia (serum phosphorus level >6.0 mg/dL) underwent a two-week washout period and were randomly selected to receive sevelamer hydrochloride (n = 37) or calcium acetate (n = 33) for eight weeks. Changes in serum levels of intact parathyroid hormone (iPTH), alkaline phosphatase (Alk-P), phosphorus, and calcium were measured and compared. RESULTS: After eight weeks of treatment, calcium acetate lowered iPTH levels significantly more than sevelamer hydrochloride did (-178.0 vs. -69.0 pg/mL, p = 0.0019). Levels of Alk-P were significantly elevated in patients given sevelamer hydrochloride compared with levels in those given calcium acetate treatment (24.09 vs. 7.45 U/L, p = 0.0014). Changes in serum phosphorus levels did not differ between sevelamer hydrochloride (-1.93 mg/dL) and calcium acetate (-2.5 mg/dL) at the end of the study (p = 0.0514). Changes in the calcium and phosphorous product did not significantly differ between the sevelamer-hydrochloride group (-18.06 mg2/dL2) and the calcium-acetate group (-19.05 mg2/dL2, p = 0.6764). Fifteen patients (45.5%) treated with calcium acetate had hypercalcemia (serum-adjusted calcium level >10.5 mg/dL); the rate was significantly higher than that of patients treated with sevelamer (five [13.5%] of 37, p = 0.0039). CONCLUSION: Treatment with sevelamer hydrochloride had the advantage of maintaining stable iPTH levels and elevating Alk-P levels while lowering serum phosphorus levels and calcium-phosphorous product.