This invention relates to lysine isotopologues of Formulas I and 1-A, as described herein, and processes for synthesizing the same and derivatives and intermediates involved therein. In one aspect, described herein is a chemical compound comprising an isotopically labeled analog, i.e., an isotopologue of a standard or naturally occurring lysine. The lysine isotopologue is synthetically formed to have stable isotopes of elements incorporated at selected positions. As such, the lysine isotopologue has a molecular mass different from the mass of a standard or naturally occurring lysine.

Some aspects of the invention provide for essential fatty acids which are substituted in specific positions to slow down oxidative damage by Reactive Oxygen Species (ROS), and to suppress the rate of consequent formation of reactive products, for the purpose of preventing or reducing the damage associated with oxidative stress associated diseases such as neurological diseases and age-related macular degeneration (AMD).

Provided herein are brain penetrant histone deacetylase (HDAC) inhibitors useful for treating diseases or disorders associated with HDAC. An exemplary HDAC inhibitor provided herein exhibits a brain-to-plasma ratio of 20:1. Pharmaceutical compositions comprising HDAC inhibitors and methods for treating diseases associated with HDAC are also provided.

The present specification relates to a method for analyzing deuterated benzene by gas chromatography, and preparing a deuterated compound using deuterated benzene selected based on the analyzed data.

The invention provides a compound capable of improving more the capabilities of organic EL devices, an organic electroluminescent device having more improved device capabilities, and an electronic device including such an organic electroluminescent device. The compound is represented by the following formula (1):

##STR00001## ##STR00002##

wherein N*, *a1 to *a3, *b1 to *b3, m1 to m3, n1 to n3, R.sup.1A to R.sup.5A, R.sup.1B to R.sup.5B, R.sup.11A to R.sup.15A, R.sup.11B to R.sup.15B, R.sup.21A to R.sup.25A, R.sup.21B to R.sup.25B, R.sup.31 to R.sup.35, R.sup.36 to R.sup.38, R.sup.39 to R.sup.42, R.sup.43 to R.sup.47, Ar.sup.1 and Ar.sup.2 are as defined in the specification; the organic electroluminescent device includes the compound; and the electronic device includes such an organic electroluminescent device.

A positron emission tomography (PET) radiotracer for imaging lactate uptake, wherein the tracer is [.sup.18F]-3-fluoro-2-hydroxypropionic acid, or a pharmaceutical acceptable salt and/or solvate thereof. Also, a process for the radiosynthesis of [.sup.18F]-3-fluoro-2-hydroxypropionic acid, or a pharmaceutical acceptable salt and/or solvate thereof. Further, the use of [.sup.18F]-3-fluoro-2-hydroxypropionic acid, or a pharmaceutical acceptable salt and/or solvate thereof, for imaging lactate uptake in living cells, especially in humans.

The present invention provides an organic EL device having at least an anode, a hole injection layer, a first hole transport layer, a second hole transport layer, a luminous layer, an electron transport layer, and a cathode in order of description. The second hole transport layer includes an arylamine compound having a specific structure, and the electron transport layer includes a pyrimidine derivative having a specific structure. The organic EL device of the present invention has a high efficiency, a low driving voltage, and a longer life.

Provided is a compound of Formula (I):

##STR00001## wherein the variable groups are defined herein.

Provided are a light-emitting device including a diamine compound represented by Formula 1, an electronic apparatus including the light-emitting device, and a diamine compound represented by Formula 1, wherein details of Formula 1 are the same as described in the detailed description:

##STR00001##

According to the present invention, a deuterium-substituted marker for fuel is synthesized through substitution with deuterium so as to have structurally and chemically similar properties to those of a molecule configuring fuel oil. A molecule of the deuterium-substituted marker is significantly similar to the conventional molecule configuring the fuel oil, which may prevent illegal removal of the marker by the fake oil manufacturers. According to the present invention, it is able to pursue public safety and environmental protection from fake oil products, and to prevent national tax evasion, by preventing the illegal mixing of fuel oil to secure a legal distribution of the oil market according to the present invention.