Millimeter- and submillimeter-wave spectra of AuCl and AuBr in the XΣ electronic ground states

The millimeter- and submillimeter-wave spectra of AuCl and AuBr in the X¹Σ⁺ states were observed by employing a source-modulated microwave spectrometer. The AuCl and AuBr molecules were, respectively, generated in a free space cell by a d.c. glow discharge in Cl₂ and Br₂ with Ar. The gold atoms were supplied by the sputtering reaction from a gold sheet placed on the inner surface of a stainless-steel cathode. Rotational transitions of , , , and in highly excited vibrational states as well as in the ground vibrational states were measured in the region between 189 and 314 GHz. The transition frequencies were analyzed by a least-squares method using a combined-isotopomer Dunham-type term energy expression. The potential constants of gold halides obtained were compared with those of copper and silver halides.     

Hochschild Cohomology of <Emphasis Type="Italic">q</Emphasis>-Schur Algebras

We compute the Hochschild cohomology of any block of q-Schur algebras. We focus on the even part of this Hochschild cohomology ring. To compute the Hochschild cohomology of q-Schur algebras, we prove the following two results: first, we construct two graded algebra surjections between the Hochschild cohomologies of quasi-hereditary algebras because all q-Schur algebras over a field are quasi-hereditary. Second, we give the graded algebra isomorphism of Hochschild cohomologies by using a certain derive equivalence.     

Palladium(0)-catalyzed regioselective and multicomponent synthesis of 1,2,3-trisubstituted 1H-indenes

A multicomponent synthesis of biologically important indenes bearing three substituent groups at the 1-, 2-, and 3-positions from available o-ethynylbenzaldehyde derivatives and organoboron reagents under palladium(0) catalysis is described. A two-component coupling reaction in methanol provides 1H-indenols, whereas a three-component reaction involving secondary aliphatic amines as the third component in DMF affords 1H-indenamines. This method allows combinatorial preparation of unsymmetrically substituted 1H-indenes that cannot be prepared via previous synthetic routes.     

Radical fixation of functionalized carbon resources: alpha-sp3C-H carbamoylation of tertiary amines with aryl isocyanates

A new carbamoylation of tertiary amines is reported. This rare C-H transformation features the direct generation of alpha-aminoalkyl radicals from tertiary amines, followed by the addition of the resultant nucleophilic radicals to isocyanates, enabling unique access to N,N-dialkylated amino acid derivatives. The authors put forward a mechanistic proposal that is based on the isolation of borinamides produced by capturing nitrogen radical intermediates with Et3B. The present transformation provides a novel one-step process for producing mepivacaine, a clinically important local anesthetic, from readily available materials.     

Magneto-photoluminescence study of InGaAs quantum dots fabricated by droplet epitaxy

We have successfully measured magneto-photoluminescence of InGaAs quantum dots (QDs) fabricated by droplet epitaxy with highly dense Ga droplets, termed separated-phase enhance epitaxy with droplets (SPEED). In the low magnetic field region, the PL peak energy shift increases linearly with square of the magnetic field. From the estimated Bohr radii for the QDs, it is found that the size of the QDs in the lateral direction is 2.7-times larger than that in the vertical direction. Moreover, using high magnetic region for estimating the detailed lateral size, the cyclotron radius around 25 T in the QDs becomes equal to the lateral size of the QDs. The cyclotron radius of 5.1 nm at 25 T suggests that the size of the InGaAs QDs in lateral direction might be as small as about 10 nm.     

Determination of serum <Emphasis Type="SmallCaps">d</Emphasis>-lactic and <Emphasis Type="SmallCaps">l</Emphasis>-lactic acids in normal subjects and diabetic patients by column-switching HPLC with pre-column fluorescence derivatization

d-Lactic and l-lactic acids were simultaneously determined by means of a column-switching high-performance liquid chromatography (HPLC) with fluorescence detection. As a fluorescence reagent, 4-nitro-7-piperazino-2,1,3-benzoxadiazole (NBD-PZ) was employed for the fluorescence derivatization of lactic acid. The proposed HPLC system adopted both octylsilica (Cadenza CD-C8) and amylose-based chiral columns (CHIRALPAK AD-RH), which proved to give a sufficient enantiomeric separation of the lactic acid derivatives with a separation factor () of 1.32 and a resolution (R_s) of 1.98. Moreover, the features of the first elution of d-lactic acid peak in the proposed HPLC were convenient for the determination of trace amount of serum d-lactic acid, which is known to increase under diabetes. Intra-day and inter-day accuracies were in the range of 90.5–101.2 and 89.0–100.7%, and the intra-day and inter-day precisions were 0.3–1.2 and 0.4–4.8%, respectively. The proposed method was applied to determine d-lactic and l-lactic acids in human serum of normal subjects and diabetic patients, showing that both d-lactic and l-lactic acid concentrations were significantly increased in the serum of diabetic patients (n=31) as compared with normal subjects (n=21). This fact was found for the first time owing to the development of the proposed HPLC method which is able to determine d-lactic and l-lactic acid simultaneously. Finally, serum d-lactic acid concentrations determined by the proposed HPLC method were compared with those from a reported enzymatic assay, and the smaller p value between normal subjects and diabetic patients was shown by the proposed HPLC method.     

Synthesis and pharmacological evaluation of 2-(1-alkylpiperidin-4-yl)-n-[(1r)-1-(4-fluorophenyl)-2-methylpropyl]acetamide Derivatives as Novel Antihypertensive Agents

We synthesized and evaluated the inhibitory activity of a series of 2-(1-alkylpiperidin-4-yl)-N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]acetamide derivatives against T-type Ca(2+) channels. Structure-activity relationship studies revealed that the position of the amide structure was important for the potent inhibitory activity toward T-type Ca(2+) channels. In addition, the introduction of an appropriate substituent on the pendant benzene ring played a crucial role for the selectivity towards T-type Ca(2+) channels over L-type Ca(2+) channels and the potent bradycardic activity of these derivatives. Oral administration of N-[(1R)-1-(4-fluorophenyl)-2-methylpropyl]-2-(1-{2-[2-(2-methoxyethoxy)phenyl]ethyl}piperidin-4-yl)acetamide (4f), which had superior selectivity for T-type Ca(2+) channels over L-type Ca(2+) channels, lowered blood pressure in spontaneously hypertensive rats without inducing reflex tachycardia, which is often caused by traditional L-type Ca(2+) channel blockers.     

Asymmetric borane reduction of ketones catalyzed by N‐hydroxyalkyl‐l‐menthopyrazoles

The equimolar mixture of N‐(hydroxyalkyl)pyrazoles and borane formed boric ester complex, in which the remaining borane was stabilized by the adjacent nitrogen of thr pyrazole ring. The borane complex derived from the chiral pyrazoles such as 3‐phenyl‐l‐menthopyrazole reduced p‐methylacetophenone ( 21 ) enantioselectively. When (2′S)‐2‐(2′‐phenyl‐2′‐hydroxyethyl)‐3‐phenyl‐l‐menthopyrazole ((2′S)‐ 10b ) was used, 21 was reduced into (S)‐p‐methylphenyl‐1‐ethanol ( 22 ) in moderate chemical and optical yields. Due to the inconvenience of the preparation and the lower optical yield, the use of N‐(α‐hydroxyalkyl)pyrazoles was unpromising for the enantioselective reduction of ketones by borane.