The present application provides novel tetrahydro-isohumulone (THIAA) derivatives and substantially enantiomerically pure compositions and pharmaceutical formulations thereof. The application further provides methods of using the disclosed compounds and compositions to activate PPAR, inhibit inflammation, and treat conditions associated with inflammation and conditions responsive to PPAR modulation such as diabetes.

The invention concerns a use of C7 sugars and derivatives of formula (I), called avocado perseose, which have, inter alia, a protective activity to epidermal skin cells. These C7 sugars and derivatives are capable of maintaining the expression of markers of adult stem cells, in particular basal stem cells. Avocado perseose can also be used for preventing the deleterious effects of environmental damage. Avocado perseose has a beneficial effect on the conservation of the potential of epidermal stem cells and thus helps maintain skin homeostasis.

The invention concerns a use of C7 sugars and derivatives of formula (I), called avocado perseose, which have, inter alia, a protective activity to epidermal skin cells. These C7 sugars and derivatives are capable of maintaining the expression of markers of adult stem cells, in particular basal stem cells. Avocado perseose can also be used for preventing the deleterious effects of environmental damage. Avocado perseose has a beneficial effect on the conservation of the potential of epidermal stem cells and thus helps maintain skin homeostasis.

Reactions, reagents and process conditions for the preparation of methyl 3-bromo-2-(2,3,4,9-tetrahydro-1h-pyrido[3,4-b]indol-1-yl)propanoate.

Reactions, reagents and process conditions for the preparation of methyl 3-bromo-2-(2,3,4,9-tetrahydro-1h-pyrido[3,4-b]indol-1-yl)propanoate.

A recoverable instant thickening acid and its reusing method is usable for the recycling and reusing of a gas well carbonate reservoir acidizing fluid and production stimulation operation. The recoverable instant thickening acid includes the following components in weight percentage: 1.5-3 parts of a thickener, 0.5-3 parts of potassium chloride and 100 parts of a hydrochloric acid solution, wherein the thickener is a mixture composed of a mass ratio of 40%-70% of N-lauryl-N-hydroxyethyl-N-hydroxypropyl ethylenediamine propionate or its derivatives, 4%-12% of ethanol and 18%-56% of water. With the thickening acid for performing an acidizing treatment, the residual acid solution can be re-prepared as a thickening acid for an acidizing treatment without a chemical treatment, assisting the green and environmentally friendly production and sustainable development of gas fields.

The present invention relates to a method of concentrating an aqueous solution at low pressure under a zero osmotic pressure difference condition, and more particularly, to a method of concentrating an aqueous solution containing a solute to be concentrated, at low pressure under a zero osmotic pressure difference condition. The method of the present invention comprises the steps of: (a) discharging water of a solute-containing aqueous solution to be concentrated, from a reverse osmosis separator to the outside, and transferring the concentrated aqueous solution to a zero osmotic pressure difference concentrator; (b) further concentrating the concentrated aqueous solution using the zero osmotic pressure difference concentrator comprising a feed chamber and a draw chamber, which are separated from each other by a reverse osmosis membrane or a forward osmosis membrane; and (c) recovering the solute and water from the aqueous solution further concentrated in the zero osmotic pressure difference concentrator. When the method of concentrating the aqueous solution at low pressure under the zero osmotic pressure difference condition is used, the aqueous solution can be concentrated to the maximum saturation concentration of a solute or a solution concentration of 100% using a reduced amount of energy without having to use an extraction solvent. In addition, there is an advantage in that a separate osmosis draw solution does not need to be used.

The present invention relates to a method of concentrating an aqueous solution at low pressure under a zero osmotic pressure difference condition, and more particularly, to a method of concentrating an aqueous solution containing a solute to be concentrated, at low pressure under a zero osmotic pressure difference condition. The method of the present invention comprises the steps of: (a) discharging water of a solute-containing aqueous solution to be concentrated, from a reverse osmosis separator to the outside, and transferring the concentrated aqueous solution to a zero osmotic pressure difference concentrator; (b) further concentrating the concentrated aqueous solution using the zero osmotic pressure difference concentrator comprising a feed chamber and a draw chamber, which are separated from each other by a reverse osmosis membrane or a forward osmosis membrane; and (c) recovering the solute and water from the aqueous solution further concentrated in the zero osmotic pressure difference concentrator. When the method of concentrating the aqueous solution at low pressure under the zero osmotic pressure difference condition is used, the aqueous solution can be concentrated to the maximum saturation concentration of a solute or a solution concentration of 100% using a reduced amount of energy without having to use an extraction solvent. In addition, there is an advantage in that a separate osmosis draw solution does not need to be used.

Disclosed are compounds of Formula I, including all stereoisomers and salts thereof,

##STR00001##

wherein Q.sup.1, Q.sup.2 and R are as defined in the disclosure.

Also disclosed is a method for preparing a compound of Formula I, comprising contacting a compound of Formula II

##STR00002## with a compound of Formula III

##STR00003## optionally in the presence of a catalyst or a base to form a compound of Formula I. Further disclosed is a method for preparing a compound of Formula IV,

##STR00004##

comprising reductively cyclizing a compound of Formula I in the presence of a reducing agent.

Disclosed are compounds of Formula I, including all stereoisomers and salts thereof,

##STR00001##

wherein Q.sup.1, Q.sup.2 and R are as defined in the disclosure.

Also disclosed is a method for preparing a compound of Formula I, comprising contacting a compound of Formula II

##STR00002## with a compound of Formula III

##STR00003## optionally in the presence of a catalyst or a base to form a compound of Formula I. Further disclosed is a method for preparing a compound of Formula IV,

##STR00004##

comprising reductively cyclizing a compound of Formula I in the presence of a reducing agent.