Anti-inflammatory activity of heterocyclic systems using abietic acid as starting material

A series of pyridines, pyrimidinone, oxazinones, and their derivatives were synthesized as anti-inflammatory agents using abietic acid (7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a-decahydrophenanthrene-1-carboxylic acid) as the starting material. The arylidiene derivative was treated with cyanothioacetamide to give cyano pyridine-thione, which was reacted with ethyl chloroacetate to yield the corresponding cyano ester. The ester was hydrolysed to the sodium salt, which was reacted with acetic anhydride to afford 2-methyloxazinone, which was treated with ammonium acetate to afford 2-methylpyrimidinone followed by methylation with methyl iodide to yield 2,3-dimethyl- pyrimidinone. In addition, the oxazinone derivative was reacted with aniline or hydrazine hydrate to give 3-phenyl- or 3-aminopyrimidinones. The latter reacted with thiophene-2-carboxaldehyde or phenylisothiocyanate to afford Schiff’s bases or thiosemicarbazide derivatives. The pharmacological screening showed that many of these compounds have good anti-inflammatory activity comparable to Prednisolone^® as reference drug.     

A general and efficient method for the synthesis of benzo-(iso)quinoline derivatives

A new, short and efficient synthesis of substituted benzo-(iso)quinoline derivatives is reported. The methodology is based on a Suzuki or Negishi cross-coupling followed by a cyclization reaction induced by t-BuOK in DMF to form the central ring. This approach allowed the synthesis of all four benzo-(iso)quinoline isomers and the substitution of each ring of the benzo-(iso)quinoline core.     

Lectin-based electrophoretic analysis of the expression of the 35 kDa inter-alpha-trypsin inhibitor heavy chain H4 fragment in sera of patients with five different malignancies

A 35 kDa glycoprotein whose abundance was previously demonstrated to be enhanced in sera of patients with endometrial adenocarcinoma (n = 12), was isolated from pooled sera of three of the cancer patients using champedak galactose-binding lectin affinity chromatography in the present study. Subjecting it to 2-DE and MS/MS, the glycoprotein was identified as the O-glycosylated fragment of inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4). When compared to control sera (n = 17), expression of the 35 kDa ITIH4 cleavage fragment was demonstrated to be significantly enhanced in sera of patients with breast carcinoma (n = 10), epithelial ovarian carcinoma (n = 10), and germ cell ovarian carcinoma (n = 10) but not in patients with nasopharyngeal carcinoma (n = 13) and osteosarcoma (n = 7). The lectin-based electrophoretic bioanalytical method adopted in the present study may be used to assess the physiological relevance of ITIH4 fragmentation and its correlation with different malignancies, their stages and progression.     

Improved method to determine succinylacetone in dried blood spots for diagnosis of tyrosinemia type 1 using UPLC-MS/MS

We describe an improved diagnostic method for tyrosinemia type 1 based on quantifying succinylacetone in dried blood spots by ultra-performance liquid chromatography tandem mass spectrometry. Succinylacetone extracted from a single 3/16 inch disk of specimen collection paper containing a dried blood spot was derivatized with dansylhydrazine, separated on an Acquity UPLC BEH C(18) column (2.1 x 50 mm, 1.7 microm) and detected by electrospray ionization tandem mass spectrometry. Succinylacetone derivative eluted at 0.6 min with a complete run time of 1 min. Using a 13C4 labeled succinylacetone as an internal standard, the calibration plot was linear up to 100 micromol/L with a detection limit (S/N = 3) of 0.2 micromol/L. Intra-day (n = 13) and inter-day (n = 10) variations were better than 10%. The cutoff level of succinylacetone in dried blood spots from healthy infants obtained by the current method was 0.63 micromol/L (n = 151). In dried blood spots from patients with established tyrosinemia type 1 (n = 11), concentration of succinylacetone was 6.4-30.8 micromol/L.     

Multi-screening approach to monitor and quantify 42 antibiotic residues in honey by liquid chromatography-tandem mass spectrometry

A multi-screening approach for monitoring potential chemical contaminants in honey by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) has been developed. A total of 42 veterinary drugs (5 tetracyclines, 7 macrolides, 3 aminoglycosides, 8 beta-lactams, 2 amphenicols and 17 sulfonamides) were surveyed with the ultimate goal of unambiguously confirmed and quantified these analytes at a concentration level of 20 microg/kg. A basic sample preparation including four subsequent liquid/liquid extraction steps was necessary to adequately extract the compounds of interest from the honey. The four extracts were injected into the LC-ESI-MS/MS using a stacking injection procedure. Validation of the entire procedure was carried out according to the European Union directive 2002/657/EC at three concentration levels, i.e., 10, 20 and 30 microg/kg. Good performance data were obtained for 37 analytes, out of the 42 studied. Limit of compliance and detection limit were calculated based on an internal limit set at 20 microg/kg for all the compounds and ranged between 24-30 and 27-80 microg/kg, respectively. A limited survey on honeys of different geographical origins has demonstrated that positive honey samples were often contaminated by more than one class of drugs, thus highlighting the usefulness of such multi-screening approach to ensure and warrants the quality of honey.     

Swollen and collapsed lyotropic lamellar rheology

We have investigated linear rheological properties and the structure-flow relationship of the swollen (Lam(1)) and collapsed (Lam(2)) lamellar phases, formed on didodecyldimethylammonium bromide (DDAB)/lecithin/water ternary system at 25 degrees C. Both lamellar phases behaved like Bingham fluids and showed remarkable yield stresses. At rest the Lam(1) phase, which is characterized by densely packed vesicles whose sizes increase as the water content decreases in accordance to evolution of (2)H NMR spectral profiles of D(2)O, resulted in a strong elastic gel-like response. On the other hand, the Lam(2) phase, formed at high surfactant concentrations, showed a weak-gel viscoelasticity and (2)H NMR spectral patterns which are typical of planar bilayered structures. The increase of the quadrupole splitting as the water content decreases was assumed as a strong evidence of size increasing of the lamellar domains. We have demonstrated that by using dynamic rheology and the derived relaxation time spectra, along with (2)H NMR spectra of D(2)O, it is possible to differentiate between equilibrium lamellar structures occurring in a broad interval of total surfactant concentration. In addition, a shear-thickening regime, observed at intermediate shear-rate values, highlighted the onset of out-equilibrium lamellar structures which were present both on Lam(1) and Lam(2) phases.     

Studies with 2‐arylhydrazononitriles: Further investigations on reactivity of 2‐arylhydrazononitriles towards hydroxylamine

The utilization of arylhydrazononitriles ( 6‐9 ) for synthesis of azoles is demonstrated. Thus, arylazomalononitriles ( 6 ) reacted with hydroxylamine hydrochloride to afford isoxazol‐5‐imine ( 10 ), amidoxime ( 12 ) and bis‐amidoxime ( 13 ) derivatives depending upon both the reaction conditions and molar ratio employed. 2‐Thiazolyl‐2‐arylhydrazononitriles ( 7 ) and cyanoformazans ( 8 ) gave 1,2,3‐triazole derivatives ( 15 ) and ( 17 ) respectively upon treatment with hydroxylamine hydrochloride and concomitant loss of water molecule. Formation of novel 1,2,4‐triazin‐5(4H)‐one derivatives ( 21 ) has efficiently been carried out by treatment of amidoximes ( 18 ) with acetic anhydride in acetic acid.     

Ytterbium acetate promoted asymmetric reductive amination: significantly enhanced stereoselectivity

Reductive amination of prochiral unhindered 2-alkanones 1 with (R)- or (S)-alpha-MBA in the presence of Yb(OAc)3 (50-110 mol %), Raney-Ni, and hydrogen (120 psi) results in increased diastereoselectivity for the amine products 2 (80-89% de) with good yield (80-87%). The increased de is based on comparison with the best previously reported de's when using (R)- or (S)-alpha-MBA, regardless of the strategy employed [stepwise (isolation of ketimines) or one-pot (reductive amination)], reducing agent examined, or achiral Lewis acid or Br?nsted acid examined. An in situ cis- to trans-ketimine isomerization mechanism, promoted by Yb(OAc)3, has been proposed to account for the observed increase in diastereoselectivity and suggests a new entry into the control of ketimine geometry.     

A new thermal study of the reaction of 6‐azidopyridones with different amines and hydrazines

Reacting of 6‐azidopyridone derivatives 1 with o‐phenylenediamine ( 2a ) in chloroform at room temperature afforded the new azidopyridones 3 . However, its fusion with 2a,b at 100–110°C gave the interesting pyrido[2,3‐b][1,5]diazepines 4a,b . Alternatively, compound 4a could also be obtained by heating azidopyridones 3 at 100–110°C. When compound 1 was allowed to react with hydrazines 7a‐d at room temperature it gave the corresponding azido compounds 8a‐d . Fusion of 1 with phenylhydrazine ( 7d ) at 140–160°C afforded the new aminopyridones 10 . The 6‐azidopyridones 1 could also be converted to the corresponding 6‐alkylaminopyridones 15a‐d by reaction with an excess of alkylamines at room temperature.     

Fused polyaza‐heterocycles and 1,3,4‐thiadiazoles via a tricyano synthon

Treatment of 2‐cyano‐3‐phenyl‐2‐pentenedinitrile with some heterocyclic diazonium salts afforded the corresponding heterocyclic hydrazones. Some of the latter hydrazones were converted into fused polyaza‐heterocycles upon boiling in pyridine. Reaction of 2‐cyano‐3‐phenyl‐2‐pentenedinitrile with phenylisothiocyanate gave a tricyano‐thiole derivative which on treatment with hydrazonoyl chlorides and 1‐(benzothiazol‐2‐yl)‐2‐bromoethanone furnished 1,3,4‐thiadiazole and thiazole derivatives, respectively.