The highly regio- and stereoselective 6-exo-dig mode cyclization of N-acyl-o-alkynylanilines producing 4-alkylidene-3,1-benzoxazines occurred unpredictably by use of a proper catalyst [Pd(OAc)(2)] and an effective additive (acetic acid) under suitable reaction conditions.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An efficient one-pot procedure for the synthesis of propargyl alcohol derivatives from allyl alcohol derivatives has been developed. The key to this transformation from a C–C double bond to a C–C triple bond is that hydrogen bromide elimination from 1,2-dibromoalkanes that contain a neighboring oxygen functional group is promoted by the inductive electron-withdrawing effect of the oxygen functional group. In the one-pot reaction, tetrabutylammonium hydroxide was the best base, and the addition of molecular sieves 13X also promoted the reaction.
A method was established to isolate the glomeruli from the kidney fixed in formaldehyde. O-Hydroxylysylglycosides and hydroxyproline in the isolated glomeruli from the kidney of normal subjects, diabetics and subjects with chronic glomerulonephritis were measured on the alkaline hydrolyzate of the glomeruli. O-Hydroxylysylglycosides in 1000 glomeruli were 9.42 +/- 2.68 nmoles (mean +/- S.D.) for controls, 12.92 +/- 7.36 nmoles for diabetics and 12.54 +/- 4.62 nmoles for subjects with chronic glomerulonephritis. Hydroxyproline in 1000 glomeruli from control, diabetics and subjects with chronic glomerulonephritis was 43.0 +/- 10.7, 82.0 +/- 39.3 and 52.1 +/- 21.3 nmoles, respectively. Hydroxyproline in the hyalinized glomeruli from diabetics was 123.3 +/- 22.4 nmoles/1000 glomeruli, and significantly increased in comparison with that in the glomeruli from chronic glomerulonephritis or control subjects.
Diamond-like carbon (DLC) films are metastable amorphous carbon materials with superior tribological characteristics. In order to improve wear resistance of micro-extrusion dies with numerous imperceptible holes, DLC films were deposited on the inner wall surface of model dies with holes of 2 mm, 0.9 mm in diameter and 20 mm in depth by using pulse plasma CVD method. This paper will discuss that Argon gas, deposition pressure and time how to affect the, characteristics of films deposited on the inner wall surface of dies.
