Abstract: A process for preparing optically pure decahydroisoquinolines in good yields which avoids difficult purification procedures is described.

Abstract: An efficient process for the preparation of styrylbenzoxazoles and derivatives thereof comprises reacting a methylbenzoxazole with an aromatic aldehyde in the presence of strong base at low temperature, followed by warming. The condensation products are inhibitors of H.sup.+ K.sup.+ -ATPase, and are also useful as penultimate compounds in the preparation of inhibitors of HIV reverse transcriptase.

Abstract: An intermediate, useful in the conversion of FK-506 to FK-525 and analogous 23-membered ring macrolides, of the structure: ##STR1##

Abstract: The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from nitrogen deprotected 4-furanylazetidin-2-ones.

Abstract: A process for the conversion of FK-506 (I,R=allyl;1) to FK-525 (XV) and analogous 23-membered ring macrolides differing in the C.1-N.7 segment of the molecule (e.g. XVI) and is also applicable to the analogs FK-523 (XVII) and FK-520 (XVIII). The overall process consists of three stages: (a) initial degradation of the primary macrolide to an acyclic fragment containing a selectively protected C.10-C.34 framework with a protected aldehyde function at C.10 and a free hydroxyl function at C.26, (b) reacylation of the C.26 hydroxyl function with an appropriately N-protected alpha-amino acid moiety, and (c) reintroduction of the C.8 and C.9 carbons followed by regeneration of the FK-macrolide system.

Abstract: A process is described for the stereocontrolled synthesis of (3R,4R)-3-[(1R)-1-hydroxyethyl]-4-benzoyloxyazetidin-2-ones and their derivatives by cycloaddition involving an imine and a ketone, generated from 3(S)-hydroxybutyrate which are useful intermediates in the synthesis of carbapenem antibiotics.

Abstract: A process is described for the synthesis of diastereomeric 2-methyl-4-hydroxy-5-protected-hydroxy-hept-6-en-prolinolamides, which are useful as intermediates in the synthesis of the C.sub.10 -C.sub.18 chain of the macrolide structure for the immunosuppressant FK-506. These compounds are also useful as intermediates for preparing lactone ultraviolet radiation absorbers.

Abstract: A unique process for preparing certain (2R-trans)hexahydroaroquinolizines, especially (2R-trans)-N-[2-(1,3,4,6,7,12b-hexahydro-2'-oxospiro[aro-[2,3-a]-quinolizi ne-2,4'-imidazolidin]-3'-yl) ethyl)-methanesulfonamide from (2R-trans)-N-[2-[(2-cyano-(1,3,4,6,7,12b-hexahydro-aro-[2,3-a]quinolizin-2 -yl)amino]ethyl]methanesulfonamide is described.

Abstract: This invention discloses novel intermediates and novel process for their preparation where said intermediates are useful for the preparation of 5-oxygenated derivatives (T) of lovastatin and analogs thereof at the 8-acyl side chain and 6-position of the polyhydronaphthyl ring. Said derivatives of lovastatin (T) and analogs thereof are useful in treating hypercholesterolemia and are disclosed in the U.S. Pat. No. 4,963,538.

Abstract: A process is described involving an alkaline rearrangement of FK-506 producing a new decarbonylated 22-membered macrocycle rearrangement derivative of FK-506, i.e. C.9, nor-keto FK-506.

Abstract: The 4-acryloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by electrochemical methods.

Abstract: A unique process for preparing certain (2R-trans)hexahydroaroquinolizines, especially (2R-trans)-N-[2-(1,3,4,6,7,12b-hexahydro-2'-oxospiro[aro-[2,3-a]-quinolizi ne-2,4'-imidazolidin]-3'-yl)ethyl)-methanesulfonamide from (2R-trans)-N-[2-[(2-cyano-(1,3,4,6,7,12b-hexahydro-aro-[2,3-a]quinolizin-2 -yl)amino]ethyl]methanesulfonamide is described.

Abstract: The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by singlet oxygen oxidation.

Abstract: A process is described for the synthesis of hydroxy lactone 3, being 1R, 2R, 5R-2-hydroxy-6-oxo-7-oxabicyclo[3.2.1]-octane, in optically pure form, which is useful as an intermediate in the synthesis of the C.sub.20 -C.sub.34 chain of the macrolide structure for the immunosuppressant FK-506. This compound is also useful as a precursor for producing an ultraviolet radiation absorber.

Abstract: The 4-acyloxyazetidin-2-ones, which are intermediates in the production of carbapenems and penems, are produced from 4-furanylazetidin-2-ones by a sequential oxidation-reduction-oxidation reaction scheme.

Abstract: A process is described involving an alkaline rearrangement of FK-506 producing a new decarbonylated 22-membered macrocycle rearrangement derivative of FK-506, i.e. C.9, nor-keto FK-506.

Abstract: A process is described for the synthesis of E-2-methyl-.alpha.,.beta.-unsaturated aldehydes, which are useful as intermediates in the synthesis of the macrolide structure of the immunosuppressant FK-506. These compounds are also useful as ultraviolet radiation absorbers.

Abstract: A process for producing arylglyoxal arylimine intermediates, by the DMSO/HBr oxidation of arylmethylketones. The imine compounds are intermediates in the synthesis of carbapenem antibiotics, i.e. imipenem.

Abstract: The present invention is directed to an enantioselective synthesis of 1,3,4,6,7,12b(S)-hexahydro-2H-benzo[b]furo[2,3-a]quinolizin-2-one which is an intermediate in the production of the .alpha..sub.2 -adrenergic antagonist (2R,12bS)-N-(1,3,4,6,7,12-hexahydro-2H-benzo[b]furo[2,3-a]quinolizin-2-yl) -N-methyl-2-hydroxy-ethanesulfonamide hydrochloride.

Abstract: .Iaddend.hypercholesterolemic compounds of the HMG-CoA reductase type of the following general formula (1): ##STR1## involving an enantioselective aldol condensation is disclosed.