In one aspect, the invention relates to compounds having the formula I: ##STR00001##
where R.sup.1-R.sup.6 are as defined in the specification, or a pharmaceutically acceptable salt thereof. These compounds have neprilysin inhibition activity. In another aspect, the invention relates to pharmaceutical compositions comprising these compounds; methods of using these compounds; and processes and intermediates for preparing these compounds.

One embodiment of the invention provides polyisobutylene (PIB) oligomers that are end-functionalized with ruthenium (Ru) catalysts. Such nonpolar catalysts can be dissolved in nonpolar solvents such as heptane, or any other nonpolar solvent that is otherwise not latently biphasic (i.e., if two or more solvent components are present, they remain miscible with each other throughout the entire reaction process, from the addition of substrate through to the removal of product). Substrate that is dissolved in the nonpolar solvent with the catalyst is converted into product. The lower solubility of the product in the nonpolar solvent renders it easily removable, either by extraction with a more polar solvent or by applying physical means in cases where the product precipitates from the nonpolar solvent. In this manner the catalysts are recycled; since the catalysts remain in the nonpolar solvent, a new reaction can be initiated simply by dissolving fresh substrate into the nonpolar solvent.

One embodiment of the invention provides polyisobutylene (PIB) oligomers that are end-functionalized with ruthenium (Ru) catalysts. Such nonpolar catalysts can be dissolved in nonpolar solvents such as heptane, or any other nonpolar solvent that is otherwise not latently biphasic (i.e., if two or more solvent components are present, they remain miscible with each other throughout the entire reaction process, from the addition of substrate through to the removal of product). Substrate that is dissolved in the nonpolar solvent with the catalyst is converted into product. The lower solubility of the product in the nonpolar solvent renders it easily removable, either by extraction with a more polar solvent or by applying physical means in cases where the product precipitates from the nonpolar solvent. In this manner the catalysts are recycled; since the catalysts remain in the nonpolar solvent, a new reaction can be initiated simply by dissolving fresh substrate into the nonpolar solvent.

Amine N-oxide compounds having formula (I) or (II), a preparation method, and a surfactant containing the compounds:

##STR00001##

R.sup.1 is a hydrocarbon residue with 4 to 26 carbon atoms and optionally at least one O or S; R.sup.2, R.sup.3 and R.sup.5 are each hydrogen, R.sup.1O, R.sup.8 and in formula (I) also optionally CH.sub.2N.sup.+(O.sup.?)R.sup.6R.sup.6; R.sup.8 is a hydrocarbon radical with 1 to 26 carbon atoms and optionally at least one O or S; R.sup.4 is hydrogen or R.sup.8; and each R.sup.6 is a hydrocarbon radical with 1 to 6 carbon atoms and optionally at least one N, O or S. Optionally two radicals R.sup.6 on the same nitrogen atom are connected to form a five- or six-membered, nitrogen-containing ring, or optionally radical(s) R.sup.6 of a moiety N.sup.+(O.sup.?)R.sup.6R.sup.6 may be linked to radical(s) R.sup.6 of another formula (I) molecule, forming a bridge having the structure

##STR00002##

and a dimer of formula (II).

A dental composite composition is disclosed that includes a polymerizable resin, filler particles, and at least one polymerizable stable radical. A variety of polymerizable stable radicals may be employed, including those that have a 2,2,6,6-tetramethylpiperidinyl-1-oxyl moiety. Compositions as described herein exhibit excellent mechanical strength, hardness, and flexural modulus, while also significantly decreasing shrinkage stress caused by polymerization.

A dental composite composition is disclosed that includes a polymerizable resin, filler particles, and at least one polymerizable stable radical. A variety of polymerizable stable radicals may be employed, including those that have a 2,2,6,6-tetramethylpiperidinyl-1-oxyl moiety. Compositions as described herein exhibit excellent mechanical strength, hardness, and flexural modulus, while also significantly decreasing shrinkage stress caused by polymerization.

Provided are STAT3 inhibitors and methods of treating inflammation or a hyperproliferative disease such as, e.g., cancer. In some aspects, compounds may be used to treat breast cancer, a head/neck cancer, a lung cancer, a prostate cancer, or pancreatic cancer.

Disclosed in the present invention are a purification method and system of NMMO and a NMMO hydrate crystal obtained thereof. The purification method is suitable for purifying NMMO in a coagulating bath of a cellulose product, and by means of the method, almost all impurities including carbohydrate impurities can be removed from the NMMO solution of the coagulating bath of the cellulose product and a high-purity NMMO hydrate crystal is obtained. The purification method comprises the following steps: performing a cooling crystallization to the coagulating bath of the cellulose product between 20 C. and 78 C. to obtain NMMO hydrate crystals. According to the method for purifying and recovering NMMO in the coagulating bath of the cellulose product in the invention, ion-exchange resins are not needed, and acid and alkali are not needed for resin regeneration.

Disclosed in the present invention are a purification method and system of NMMO and a NMMO hydrate crystal obtained thereof. The purification method is suitable for purifying NMMO in a coagulating bath of a cellulose product, and by means of the method, almost all impurities including carbohydrate impurities can be removed from the NMMO solution of the coagulating bath of the cellulose product and a high-purity NMMO hydrate crystal is obtained. The purification method comprises the following steps: performing a cooling crystallization to the coagulating bath of the cellulose product between 20 C. and 78 C. to obtain NMMO hydrate crystals. According to the method for purifying and recovering NMMO in the coagulating bath of the cellulose product in the invention, ion-exchange resins are not needed, and acid and alkali are not needed for resin regeneration.

In one aspect, the invention relates to compounds having the formula I: ##STR00001##
where R.sup.1-R.sup.6 are as defined in the specification, or a pharmaceutically acceptable salt thereof. These compounds have neprilysin inhibition activity. In another aspect, the invention relates to pharmaceutical compositions comprising these compounds; methods of using these compounds; and processes and intermediates for preparing these compounds.