Abstract: Group A streptogramin derivatives of formula (I) and salts thereof: and Group A streptogramin derivatives of formula (III) and salts thereof: as well as processes for preparing such streptogramins, and pharmaceutical compositions comprising such streptogramins, alone or combined with at least one group B streptogramin derivative.

Abstract: The application discloses novel synthetic compounds, modeled after unique toxins extracted from the marine invertebrate Diazona angulata useful in the treatment abnormal cell mitosis. The application also discloses novel methods for synthesis of these compounds and methods of using these compounds.

Abstract: Group A streptogramin derivatives of general formula (I) in which: R1 represents a halogen atom or an azido or thiocyanato radical, R2 represents a hydrogen atom or a methyl or ethyl radical, R3 represents a hydrogen atom, or the residue of an aliphatic, cycloaliphatic, aromatic, araliphatic, heterocyclic or heterocyclylaliphatic ester which may be substituted, and the bond - - - represents a single bond (stereochemistry 27R) or a double bond, as well as its salts when they exist.

Abstract: Group A streptogramin derivatives of formula (I) and salts thereof: Group A streptogramin derivatives of formula (II) and salts thereof: and Group A streptogramin derivatives of formula (III) and salts thereof: as well as processes for preparing such streptogramins, and pharmaceutical compositions comprising such streptogramins, alone or combined with at least one group B streptogramin derivative.

Abstract: The invention provides novel polyketide compounds having desired bioactivity, including neuroregenerative activity without immunosuppressive activity, and methods of making and using these compounds.

Abstract: This invention concerns derivatives of rapamycin and their antifungal uses. Also disclosed are materials and methods relevant to the identification of non-immunosuppressive anti-fungal rapamycin derivatives.

Abstract: Group A streptogramin derivatives of formula (I) and salts thereof: 1

Abstract: Group A streptogramin derivatives of formula (I) and salts thereof: 1

Abstract: Cucurbituril derivatives, their prepartion methods and uses.

Abstract: The present invention is directed to peptidomimetic macrocyclic compounds which inhibit prenyl-protein transferase and the prenylation of the oncogene protein Ras. The invention is further directed to chemotherapeutic compositions containing the compounds of this invention and methods for inhibiting prenyl-protein transferase and the prenylation of the oncogene protein Ras.

Abstract: This invention relates to compounds of the formula ##STR1## and to pharmaceutically acceptable salts thereof. The compounds of formula 1 are potent antibacterial and antiprotozoal agents that may be used to treat various bacterial and protozoal infections and disorders related to such infections. The invention also relates to pharmaceutical compositions containing the compounds of formula 1 and to methods of treating bacterial and protozoal infections by administering the compounds of formula 1.

Abstract: Macrocyclic compounds of formula ##STR1## are potent inhibitors of matrix metalloproteinase and are useful in the treatment of diseases in which matrix metalloproteinase play a role. Also disclosed are matrix metalloproteinase inhibiting compositions and a method of inhibiting matrix metalloproteinase in a mammal.

Abstract: The invention provides novel ascomycins bearing one or more physiologically hydrolyzable and acceptable oxycarbonyl moieties or carboxy moieties, such compounds being found useful as pharmaceuticals, especially in the treatment of asthma an dermatitis. Methods of producing the compounds and pharmaceutical compositions comprising the compounds are also provided.

Abstract: Rifamycin antibiotic derivatives of formulae (I) and (Ia) bearing at the position 36 a substituent selected from (C.sub.1 -C.sub.8)alkyl, halo, hydroxy, (C.sub.1 -C.sub.4)acyloxy, (C.sub.1-C.sub.4)alkoxy, (C.sub.1 -C.sub.4)alkylthio, (C.sub.1 -C.sub.4)alkylamino, di(C.sub.1-C.sub.4)alkylamino and substituted 4-oxo-3-pyridinyl carbonyloxy of formula (1) obtained by reacting rifamycin with suitably substituted malonic acid. The compounds of the invention are antimicrobial agents mainly active against gram positive bacteria and fastidious gram negative bacteria showing the considerable antimicrobial activity against the rifamypicin resistant microbial strains.

Abstract: Macrocylic lactam compounds of formula (I) ##STR1## and pharmaceutically acceptable salts thereof, wherein A is selected from ##STR2## also disclosed are synthetic processes and intermediates useful in the preparation of the compounds of the invention, as well as compositions containing the same and methods for their use in stimulating contractile motion of the gastrointestinal tract.

Abstract: Macrocylic lactam compounds of formula (I) ##STR1## and pharmaceutically acceptable salts thereof, wherein A is selected from ##STR2## also disclosed are synthetic processes and intermediates useful in the preparation of the compounds of the invention, as well as compositions containing the same and methods for their use in stimulating contractile motion of the gastrointestinal tract.

Abstract: The present invention relates to a new one-pot process for preparing 2'-(diethylamino)rifamycin P and its 25-desacetyl derivative which consists in cyclizing 3-bromorifamycin S or its 25-desacetyl derivative, dissolved in dimethylformamide, with 1,1-diethylthiourea and reducing, without isolation, the obtained 1,2-quinonimine intermediate with a mild reducing agent.

Abstract: Described is a process for producing an immunosuppressant, "demethimmunomycin" (L-683,7411) a C-31 demethylated analog of L-683,590 under fermentation conditions utilizing the microorganism, Actinoplanacete sp, (Merck Culture Collection MA 6559) ATCC No. 53771. The macrolide immunosuppressant is useful in preventing human host rejection of foreign organ transplants, e.g. bone marrow and heart transplants.

Abstract: The insect deterrent azamacrolide ##STR1## and other insect deterrent azamacrolides have been recovered from droplets formed at the ends of pupal hairs of the Mexican bean beetle Epilachna varivestis or synthesized from (I).

Abstract: The invention relates to novel acyl derivatives of rifamycins of the formula ##STR1## and the salts thereof, in which the structural elements --A.sub.1 --A.sub.2 --, --A.sub.3 --A.sub.4 -- and --A.sub.5 --A.sub.6 -- each denote ethylene or vinylene or the elements --A.sub.1 --A.sub.2 -- and --A.sub.3 --A.sub.4 -- each denote ethylene and --A.sub.5 --A.sub.6 -- denotes vinylene; X represents >C(R.sub.6)-- or >N-- and R.sub.6 denotes hydrogen or alkyl; alk denotes an aliphatic hydrocarbon radical; R.sub.1 denotes hydrogen or acyl; R.sub.2 denotes acyl, or alkyl which is optionally substituted by an aromatic radical, and R.sub.3 and R.sub.3 ' represent a common bond, or R.sub.3 denotes hydrogen or acyl, and R.sub.3 ' is hydrogen; R.sub.4 denotes hydrogen, cycloalkyl or aryl; R.sub.5 denotes hydrogen or acetyl; R.sub.7 denotes hydrogen or alkyl, which can be used as active compounds in medicaments, the preparation and use thereof, and pharmaceutical products and the preparation thereof.

Abstract: The non-solvated crystalline form "A" of 3-(-4-cynnamyl-1-piperazinyl)-iminomethylrifamycine SV finds application in the therapeutical practice.It represents a crystalline substance with absorption maximum of the infrared spectrum at 1644, 1585, 1340, 1350, 1295 and 1290-doublet, 1238, 1213, and triplet with low intesitivety at 726, 735 and 760 cm.sup.-1, as well as with characteristic diffraction maxima at 9,25 and 9,50 .theta.--most-intensive at 12,22 and doublet at 13,10 and 13,33 .theta. of the X-ray diffraction diagram.The obtaining of the non-solvated crystalline form "A" consists in the isolation of 3-(-4-cynnamyl-1-piperazinyl)-iminomethylrifamycine obtained in medium of indifferent organic solvent, preferably tetrahydrofuran or chloroform, and its dissolution in isopropanol or acetone or a mixture of both at a temperature from 30.degree. C. up to the ebullition temperature of the respective solvent.

Abstract: Described is a new immunosuppressant, L-687,795, a C-13, C-15, C-31 trisdemethylated, ring rearranged derivative of L-683,590, produced under fermentation conditions utilizing the microorganism, Actinoplanacete sp. (Merck Culture Collection MA 6559) ATCC No. 53771. The macrolide immunosuppressant is useful in preventing human host rejection of foreign organ transplants, e.g. bone marrow and heart transplants.

Abstract: A rifamycin derivative having the formula (I): ##STR1## wherein A is a group having the formula: ##STR2## in which R.sup.1 is an alkyl group having 4 or 5 carbon atoms or an alkenyl group having 3 to 5 carbon atoms, or a group having the formula: in which n is 3 or 4; or a pharmaceutically acceptable salt thereof. The rifamycin derivative (I) exhibits a strong antibacterial activity against Gram-positive bacteria and acid-fast bacteria, and also exhibits a strong antibacterial activity against tubercle bacilli.

Abstract: Described is a new immunosuppressant, L-685,487, a monodemethylated rearranged derivative of L-683,590, produced under fermentation conditions utilizing the microorganism, unidentified Actinomycete (Merck Cultrue Collection MA 6474) ATCC No. 53828. The macrolide immunosuppressant is useful in preventing human host rejection of foreign organ transplants, e.g. bone marrow and heart transplants.

Abstract: A rifamycin derivative having the formula (I): ##STR1## wherein R.sup.1 is hydrogen atom, methyl group or ethyl group, R.sup.2 is an alkyl group having 1 to 4 carbon atoms, and A is a group having the formula: ##STR2## in which n is an integer of 3 to 5, or group having the formula: ##STR3## in which R.sup.3 is a alkyl group having 1 to 5 carbon atoms; or a salt thereof. The rifamycin derivative (I) exhibits a strong antibacterial activity against Gram-positive bacteria and acid-fast bacteria, and also exhibits a strong antibacterial activity against tubercle bacilli.

Abstract: The present invention concerns new 2'-substituted-4-deoxy-thiazolo[5,4-c]rifamycin SV derivatives having antibacterial activity.These compounds are compounds obtained by chemical modification of thiazolo[5,4-c]rifamycin SV.

Abstract: A novel rifamycin derivative having the formula (I): ##STR1## wherein X.sup.1 is an alkyl group with 1 to 6 carbon atoms or a cycloalkyl group with 3 to 8 carbon atoms; X.sup.2 is a hydrogen atom or an alkyl group with 1 to 4 carbon atoms; R.sup.1 is hydrogen atom or acetyl group; A is a group represented by the formula: ##STR2## wherein R.sup.2 is an alkyl group with 1 to 4 carbon atoms or an alkoxyalkyl group with 2 to 6 carbon atoms and R.sup.3 is an alkyl group with 1 to 6 carbon atoms or an alkoxyalkyl group with 2 to 6 carbon atoms, or a group represented by the formula ##STR3## wherein ##STR4## is a 3 to 9 membered cyclic amino group with 2 to 8 carbon atoms, R.sup.4 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, or salts thereof, a process for preparing the same and antibacterial agents containing the same as an effective ingredient.

Abstract: The present invention provides expellants of phytopothogenic microbes comprising rifamycins, which have excellent in prevention of disease in plants with little adverse influence to human body and environments.

Abstract: A novel rifamycin derivative having the general formula (I): ##STR1## or salts thereof, a process for preparing the same and antibacterial agents containing the same as an effective component.The rifamycin derivative of the present invention having the general formula (I) shows a strong antibacterial activity against the Gram-positive bacteria and the acid-fast bacteria.