133876-12-7

Upstream product

• 137071-45-5 24,33-bis-OTBDMS-ascomycin 
• 668990-41-8 C₆₁H₁₁₃NO₁₃Si₃ 
• 668990-40-7 C₆₁H₁₁₁NO₁₂Si₃ 
• 668990-42-9 C₆₁H₁₁₃NO₁₂Si₃ 
• 273752-75-3 2(R),10(S),11(S)-cyclo-ascomycin 
• 671222-63-2 11-epi-ascomycin 
• 135635-46-0 ascomycin 

Downstream Products

• 261759-01-7 17-but-1-enyl-1,14-dihydroxy-12-[2-(4-hydroxy-3-methoxy-cyclohexyl)-1-methyl-vinyl]-21,23-dimethoxy-13,17,19,25-tetramethyl-11,26-dioxa-4-aza-tricyclo[20.3.1.0^4,9]hexacosane-2,3,10,16-tetraone 
• 686773-57-9 C₄₆H₇₇NO₁₃ 
• 686773-56-8 C₄₅H₇₅NO₁₃ 
• 150250-95-6 L-733,725 
• 141281-26-7 C₅₅H₉₈N₂O₁₁Si₂ 
• 141281-25-6 C₅₅H₉₈N₂O₁₁Si₂ 
• 143360-23-0 C₄₉H₈₄N₂O₁₁Si 
• 141315-48-2 C₄₄H₇₂N₂O₁₁ 
• 261759-00-6 4-β-methoxy-9-dihydroascomycin 

Relevant academic research and scientific papers

ASCOMYCIN AND PIMECROLIMUS HAVING REDUCED LEVELS OF DESMETHYLASCOMYCIN AND 32-DEOXY-32-EPICHLORO-DESMETHYLASCOMYCIN RESPECTIVELY, AND METHODS FOR PREPARATION THEREOF

Provided is ascomycin that has a low level of an FK523 impurity, and pimecrolimus that has a low level of a 32-deoxy-32-epichloro-FK523 impurity, methods of preparing them, and the use of such pimecrolimus for preparing a pharmaceutical composition.

METHOD OF PURIFYING MACROLIDES

A method for purifying macrolide is provided in which a loading charge of macrolide is placed in juxtaposition with a bed of wet sorption resin, the loading charge and bed are eluted at a temperature greater than 30°C with an eluent of an organic solvent selected from the group consisting of THF, acetonitrile, n-propyl alcohol, iso-propyl alcohol, ethyl alcohol, and acetone, the heart cut of the eluent is collected, and purified macrolide is collected.

METHOD OF PURIFYING MACROLIDES

Provided is a method of purifying a macrolide, especially tacrolimus, that includes loading macrolide onto a bed of sorption resin and elting with a suitable eluent such as a combination of water and tetrahydrofuran.

A PROCESS FOR THE RECOVERY OF SUBSTANTIALLY PURE TRICYCLIC MACROLIDE

Process for the recovery of a macrolide in substantially pure form comprising: a) treating the macrolide with water immiscible solvent followed by concentration, b) mixing with water, water miscible solvent or mixture thereof, c) performing hydrophobic interaction chromatography and collecting the fractions, d)extracting the fraction containing macrolide with water immiscible solvent followed by concentration, e) adding water miscible solvent to effect separation of impurities from the macrolide compound, f) performing silica gel chromatography and collecting the fractions, g) isolating the macrolide compound in substantially pure form. The macrolide is preferably rapamycin, tacrolimus or immunomycin.

Selective transformation of ascomycin into 11-epi-ascomycin

Within the binding domain, ascomycin features the unusual pattern of a masked tricarbonyl moiety, which potentially allows for high structural diversity via simple isomerisation events. A cascade of diastereoselective rearrangement reactions at the binding domain, allowing the conversion of ascomycin into 11-epi-ascomycin is herein reported.

CRYSTALLIZATION AND PURIFICATION OF MACROLIDES

Provided is a method for crystallization and purification of a macrolide such as tacrolimus, sirolimus, pimecrolimus, or everolimus that includes the step of providing a combination of a macrolide, and a polar solvent, dopolar aprotic solvent, or hydrocarbon solvent at pH of 7 or above.

Regio- and stereoselective preparation of ascomycin-d1 and FK 506-d1

The immunosuppressive macrolides ascomycin 1 and FK 506 2 were stereoselectively deuteriated at C(32) using Curran's radical translocating method. Both AIBN and Et3B/O2 were tested as radical initiator for the radical translocation/reduction step with Bu3SnD as reducing agent. Despite only minor structural differences, ascomycin and FK 506 showed remarkably different behaviour under the radical translocation/reduction conditions. Higher stereoselectivities were observed with Et3B/O2 as initiator, presumably due to lower reaction temperatures applied in this case. Copyright

Selective epimerization and skeletal resection in the ascomycin framework: A study of the biological consequences of lactam rotamer selection

Ascomycin (1a), a macrolactam antifungal antibiotic disclosed by Arai in 1962, was found to display immunosuppressive activity more than 2 decades later by Okuhara and coworkers at Fujisawa. Ascomycin (1a) and FK506 (1b) bind to a peptidyl-prolyl-isomerase, FKBP, a necessary but insufficient condition for drug activity. Both FK506 and ascomycin exist as a mixture of slowly interconverting cis and trans amide rotamers. It has also been shown that only the trans amide rotamer binds to FKBP. 24-epi-Ascomycin (3), 24- oxo-22-norascomyin (9a), and 22-norascomycin (9b), obtained by semisynthesis from ascomycin, exist as single rotamers on the NMR time scale. Their synthesis and the biological consequences of this observation are discussed.