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Combinatorial synthesis and high-throughput characterization of a Ni-Ti-Co thin film materials library are reported for exploration of reversible martensitic transformation. The library was prepared by magnetron co-sputtering, annealed in vacuum at 500 °C without atmospheric exposure, and evaluated for shape memory behavior as an indicator of transformation. Composition, structure, and transformation behavior of the 177 pads in the library were characterized using high-throughput wavelength dispersive spectroscopy (WDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and four-point probe temperature-dependent resistance (R(T)) measurements. A new, expanded composition space having phase transformation with low thermal hysteresis and Co > 10 at. % is found. Unsupervised machine learning methods of hierarchical clustering were employed to streamline data processing of the large XRD and XPS data sets. Through cluster analysis of XRD data, we identified and mapped the constituent structural phases. Composition-structure-property maps for the ternary system are made to correlate the functional properties to the local microstructure and composition of the Ni-Ti-Co thin film library.

6 beta-[(1-Substituted-4-pyridinio)amino]penam-3-carboxylates and 7 beta-[(1-substituted-4-pyridinio)amino]ceph-3-em-4-carboxylates have been found to be interesting new classes of antibacterial beta-lactams, readily available by SN2 Ar coupling of fluoro-substituted quaternized pyridines and appropriate amino lactam carboxylic acids. Compared to penicillin G, the penam 12c exhibited a spectrum extended to Gram-negative species, such as Escherichia, Shigella, Klebsiella and Enterobacter, offset by a loss of potency against Gram-positive species. Excluding Pseudomonas, many examples of the cephems showed excellent activity against the above Gram-negative organisms, and in some cases, such as 15i, the spectrum included good performance against the staphylococci and streptococci. With Serratia and many Proteus species, there was an adverse inoculum and medium effect which was not observed in the good Gram-positive reach of the cephem series.

Reaction of methyl 2,3-anhydro-5- O -trityl-β- d -ribofuranoside ( 4 ) with methyl-magnesium chloride gave a mixture of methyl 3-chloro-3-deoxy-5- O -trityl-β- d -xylofuranoside ( 5 ) and methyl 3-deoxy-3- C -methyl-5- O -trityl-α- d -xylofuranoside ( 6 ). Removal of the trityl group from 6 gave methyl 3-deoxy-3- C -methyl-β- d -xylofuranoside ( 9 ), which, on treatment with p -nitrobenzoyl chloride, gave methyl 3-deoxy-3- C -methyl-2,5-di- O -( p -nitrobenzoyl)-β- d -xylofuranoside ( 10 ). The glycosyl chloride ( 15 ) derived from 10 reacted with 6-(benzamido)chloromercuripurine to give 6-(benzamido)-9-[3-deoxy-3- C -methyl-2,5-di- O -( p -nitrobenzoyl)- d -xylofuranosyl]purine ( 16 ). Alkaline methanolysis of 16 produced 9-(3-deoxy-3- C -methyl-α- d -xylofuranosyl)-adenine (α- 1 ) and 9-(3-deoxy-3- C -methyl-β- d -xylofuranosyl)adenine (β- 1 ) in the ratio of 1:4. Treatment of 6 with benzoyl chloride gave methyl 2- O -benzoyl-3-deoxy-3- C -methyl-5- O -trityl-β- d -xylofuranoside ( 17 ). The trityl group was removed from 17 to give methyl 2- O -benzoyl-3-deoxy-3- C -methyl-β- d -xylofuranoside ( 18 ), which was converted into methyl 2,5-di- O -benzoyl-3-deoxy-3- C -methyl-β- d -xylofuranoside ( 19 ). When the glycosyl halide ( 20 ) obtained from 19 reacted with 6-(benzamido)chloromercuripurine, 6-(benzamido)-9-(2,5-di- O -benzoyl-3-deoxy-3- C -methyl- d -xylofuranosyl)-purine ( 21 ) was produced. Ammonolysis of 21 gave α- 1 and β- 1 in the ratio of 1:16.

Cyclopropanation of acrylonitrile (I) with ethyl diazoacetate (II) gives the diastereomeric cyclopropanes (III) which are reduced, yielding the amino alcohols (IV).

A series of steroids, primarily 4-azasteroids, were prepared and tested in vitro as inhibitors of human and rat prostatic 5 alpha-reductase and of binding of dihydrotestosterone to the rat androgen receptor. The primary structural modifications were changes of the A ring and of moieties attached at the C-17 position of the steroid nucleus. New A-ring modifications included the 4-cyano-3-oxo-delta 4 system in the carbocyclic series and 1 alpha-CN, 1 alpha-CH3, 1 alpha,2 alpha-CH2, 2 beta-F, 2-aza, 2-oxa, and A-homo changes in the 3-oxo-4-aza series. In addition, 4-azasteroids with a D-homo ring or methyl substitution at C-7 (alpha and beta) or C-16 (alpha and beta) were prepared. The majority of the C-17 substituents were prepared from reactive intermediates derived from the 17 beta-COOH. Enhanced 5 alpha-reductase inhibition in both the human and rat enzyme assays is seen with 4-CN substitution on 3-oxo-delta 4 steroids and with a C-17 side chain incorporating a lipophilically substituted semipolar group on the 4-aza-3-oxo-5 alpha-androstane nucleus. Fewer highly active compounds were found in the human enzyme assay than in the rat assay. Structural requirements for inhibition of the rat androgen receptor are much different from those for inhibition of the enzyme. The 17 beta-OH moiety enhances potency more than any other feature while introduction of double bonds at C-1 or C-5 in the azasteroid gives a small improvement. Azasteroids unsubstituted at the 4-position show greatly diminished receptor activity.