Abstract: A process is provided for preparing azetidinones useful as intermediates in the synthesis of penems and as hypocholesterolemic agents, comprising reacting a ?-(substituted-amino)amide, a ?-(substituted-amino)acid ester, or a ?-(substituted-amino)thiolcarbonic acid ester with a silylating agent and a cyclizing agent selected from the group consisting of alkali metal carboxylates, quaternary ammonium carboxylates, quaternary ammonium hydroxides, quaternary ammonium alkoxides, quaternary ammonium aryloxides and hydrates thereof, or the reaction product of: (i) at least one quaternary ammonium halide and at least one alkali metal carboxylate; or (ii) at least one quaternary ammonium chloride, quaternary ammonium bromide, or quaternary ammonium iodide and at least one alkali metal fluoride, wherein a quaternary ammonium moiety of the cyclizing agent is unsubstituted or substituted by one to four groups independently selected from the group consisting of alkyl, arylalkyl and arylalkyl-alkyl.

Abstract: A process is provided for preparing azetidinones useful as intermediates in the synthesis of penems and as hypocholesterolemic agents, comprising reacting a ?-(substituted-amino)amide, a ?-(substituted-amino)acid ester, or a ?-(substituted-amino)thiolcarbonic acid ester with a silylating agent and a cyclizing agent selected from the group consisting of alkali metal carboxylates, quaternary ammonium carboxylates, quaternary ammonium hydroxides, quaternary ammonium alkoxides, quaternary ammonium aryloxides and hydrates thereof, or the reaction product of: (i) at least one quaternary ammonium halide and at least one alkali metal carboxylate; or (ii) at least one quaternary ammonium chloride, quaternary ammonium bromide, or quaternary ammonium iodide and at least one alkali metal fluoride, wherein a quaternary ammonium moiety of the cyclizing agent is unsubstituted or substituted by one to four groups independently selected from the group consisting of alkyl, arylalkyl and arylalkyl-alkyl.

Abstract: A process is provided for preparing azetidinones useful as intermediates in the synthesis of penems and as hypocholesterolemic agents, comprising reacting a ?-(substituted-amino)amide, a ?-(substituted-amino)acid ester, or a ?-(substituted-amino)thiolcarbonic acid ester with a silylating agent and a cyclizing agent selected from the group consisting of alkali metal carboxylates, quaternary ammonium carboxylates, quaternary ammonium hydroxides, quaternary ammonium alkoxides, quaternary ammonium aryloxides and hydrates thereof, or the reaction product of: (i) at least one quaternary ammonium halide and at least one alkali metal carboxylate; or (ii) at least one quaternary ammonium chloride, quaternary ammonium bromide, or quaternary ammonium iodide and at least one alkali metal fluoride, wherein a quaternary ammonium moiety of the cyclizing agent is unsubstituted or substituted by one to four groups independently selected from the group consisting of alkyl, arylalkyl and arylalkyl-alkyl.

Abstract: This application discloses provides a process for the introduction of nitro-group functionality into a compound which contains also a site of unsaturation and/or oxygen functionality by direct (one step) oxidation of an oxime functional group mediated by a molybdenum VI/VII peroxo complex, the process comprising: (a) providing a substrate of Formula I containing an oxime functional group; wherein R1 and R2 are selected independently from linear, branched or cyclic alkyl and linear, branched or cyclic alkenyl groups, optionally substituted, with the proviso that at least one of R1 or R2 contains a carbon/carbon double bond; and (b) contacting said substrate of Formula I with a molybdenum oxidation complex, thereby oxidizing said oxime functional group to a nitro functional group to yield the structure of Formula III. Where R1 and R2 are as defined above.

Abstract: The present invention relates to an improved process for preparing himbacine analogs. The compounds are useful as thrombin receptor antagonists. The improved process may allow for at least one of easier purification by crystallization, easier scalability, and improved process yield on the desired enantiomer.

Abstract: This application discloses provides a process for the introduction of nitro-group functionality into a compound which contains also a site of unsaturation and/or oxygen functionality by direct (one step) oxidation of an oxime functional group mediated by a molybdenum VI/VII peroxo complex, the process comprising: (a) providing a substrate of Formula I containing an oxime functional group; wherein R1 and R2 are selected independently from linear, branched or cyclic alkyl and linear, branched or cyclic alkenyl groups, optionally substituted, with the proviso that at least one of R1 or R2 contains a carbon/carbon double bond; and (b) contacting said substrate of Formula I with a molybdenum oxidation complex, thereby oxidizing said oxime functional group to a nitro functional group to yield the structure of Formula III. Where R1 and R2 are as defined above.

Abstract: The present invention relates to an improved process for preparing himbacine analogs. The compounds are useful as thrombin receptor antagonists. The improved process may allow for at least one of easier purification by crystallization, easier scalability, and improved process yield on the desired enantiomer.

Abstract: This application discloses provides a process for the introduction of nitro-group functionality into a compound which contains also a site of unsaturation and/or oxygen functionality by direct (one step) oxidation of an oxime functional group mediated by a molybdenum VI/VII peroxo complex, the process comprising: (a) providing a substrate of Formula I containing an oxime functional group; ?wherein R1 and R2 are selected independently from linear, branched or cyclic alkyl and linear, branched or cyclic alkenyl groups, optionally substituted, with the proviso that at least one of R1 or R2 contains a carbon/carbon double bond; and (b) contacting said substrate of Formula I with a molybdenum oxidation complex, thereby oxidizing said oxime functional group to a nitro functional group to yield the structure of Formula III. Where R1 and R2 are as defined above.

Abstract: The present invention relates to an improved process for preparing himbacine analogs. The compounds are useful as thrombin receptor antagonists. The improved process may allow for at least one of easier purification by crystallization, easier scalability, and improved process yield on the desired enantiomer.

Abstract: A crystalline polymorph of a bislulfate salt of a thrombin receptor antagonist compound, which exhibits a powder x-ray diffraction profile substantially the same as that shown in FIG. 1, or which exhibits a differential scanning calorimtery profile substantially the same as that shown in FIG.

Abstract: Method and apparatus for generating sinusoidal signals in quadrature. A numerically controlled oscillator includes a phase accumulator configured to generate a periodic multi-bit signal at a given frequency; a first memory configured to store an octant of a sinusoidal waveform; a second memory configured to store a complementary octant of the sinusoidal waveform; and a control circuit, responsive to at least a portion of the phase accumulator signal and coupled to the first and second memories, the control circuit configured to access the first and second memories in parallel and construct respective sine and cosine waves at the given frequency.

Abstract: This invention provides a process for preparing the hypocholesterolemic compound comprising: (a) reacting p-fluorobenzoylbutyric acid with pivaloyl chloride and acylating the product with a chiral auxiliary to obtain a ketone of formula IV: (b) reducing the ketone of formula IV in the presence of a chiral catalyst to an alcohol: (c) reacting the chiral alcohol of step (b), an imine and a silyl protecting agent, then condensing the protected compounds to obtain a &bgr;-(substituted-amino)amide of formula VII: (d) cyclizing the &bgr;-(substituted-amino)amide of formula VII with a silylating agent and a fluoride ion catalyst to obtain a protected lactam of the formula VIII: and removing the protecting groups. The intermediates of formulas VII and VIII are also claimed.

Abstract: There is disclosed a novel formylating agent, 2-formylmercaptobenzothiazole.

Abstract: An improved process for converting gentamicin B to isepamicin comprising forming 3,6'-di-N-formylgentamicin B, acylating the 1-amino group with an N-protected (S)-isoserine compound and removing all the blocking groups under conditions which result in high yields of isepamicin. A novel formylating agent, 2-formylmercaptobenzothiazole, and intermediate compounds are also disclosed.

Abstract: A high yielding process for converting 3,2',6'-tri-N-acetyl sisomicin to netilmicin comprising the step of silylating the starting material at the 5,2' positions, and optionally at the 4' position, converting the 1-amino substituent to a 1-N-imino substituent, converting the imino to an ethylamino, deprotecting the compound and recovering netilmicin. Also disclosed are novel intermediate compounds.

Abstract: A novel, stable, crystalline sodium (5R,6S,8R)-6-(1-hydroxyethyl)-2-(2-carbamoyloxyethylthio)-penem-3-carboxyl ate (designated as Form II) is prepared by forming a homogenous solution of sodium (5R,6S,8R)-6-(1-hydroxyethyl)-2-(2-carbamoyloxyethylthio)-penem-3-carboxyl ate combined with stirring the homogenous solution for a time and at a temperature sufficient to produce Form II and recovering Form II. Form II may also be prepared by contacting a first solution obtained by dissolving (5R,6S,8R)-6-(1-hydroxyethyl)-2-(2-carbamoyloxyethylthio)-penem-3-carboxyl ic acid in dimethylacetamide with a second solution obtained by dissolving a sodium salt of an organic acid having a pKa of up to about 5, e.g., sodium 2-ethylhexanoate in acetone, in the presence of at least 5 volume percent water while stirring the reaction mixture so formed at a temperature and for a time sufficient to produce Form II followed by recovering Form II.