Abstract: The invention provides antitumour compounds of formula (I), wherein R1 is an aromatic substituent; R2 is hydrogen or a substituent when the dotted line is absent, or R2 is absent when the dotted line represents a bond to give a double bond between the nitrogen which bears R2 and the carbon which bears R3; R3 is an oxo group ?O when the dotted line is absent or is a substituent when the dotted line represents a bond to give a double bond between the nitrogen bearing R2 and the carbon bearing R3; R4 is hydrogen or a substituent; and pharmaceutically acceptable salts thereof.

Abstract: Naturally occurring stolonoxide compounds, and derivatives thereof, have antitumor activity.

Abstract: The invention provides antitumour compounds of formula (I), wherein R1 is an aromatic substituent; R2 is hydrogen or a substituent when the dotted line is absent, or R2 is absent when the dotted line represents a bond to give a double bond between the nitrogen which bears R2 and the carbon which bears R3; R3 is an oxo group ═O when the dotted line is absent or is a substituent when the dotted line represents a bond to give a double bond between the nitrogen bearing R2 and the carbon bearing R3; R4 is hydrogen or a substituent; and pharmaceutically acceptable salts thereof.

Abstract: Citreamicins possess useful antitumor activity. Typically they are of formula, wherein R1 is selected from the group consisting of COCH2CH(CH3)2, COCH3 or H when R2 is CH3, or wherein R1 is COCH2CH(CH3)2, and R2 is H.

Abstract: Compounds of the following formula: wherein all variables are as defined in the specification. The compounds have cytotoxic properties and can therefore be used in the treatment of malignant tumors.

Abstract: Naturally occuring stolonoxide compounds, and derivatives thereof, have antitumour activity. Typical compounds are of the formula (I) or a derivative thereof.

Abstract: The invention provides compounds of formula (I) wherein R1 represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, a hydroxy group, an alkoxy group having from 1 to 6 carbon atoms, a halogen atom, a nitro group, an amino group, a monoalkylamino group wherein the alkyl moiety has from 1 to 6 carbon atoms, a dialkylamino group wherein each alkyl moiety may be the same or different and each has from 1 to 6 carbon atoms, a dialkoxyamino group wherein each alkoxy moiety may be the same or different and each has from 1 to 6 carbon atoms, an alkanoyalmino group having from 1 to 20 carbon atoms or an alkanesulfonylamino group having from 1 to 6 carbon atoms; R2 represents a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms; and R3 represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms or an alkoxy group having from 1 to 6 carbon atoms; and pharmaceutically acceptable salts thereof.

Abstract: Compounds of formula (I), wherein X is selected from the group consisting of O, and NR3, where R3 represents a lower alkyl group; Y is selected from the group consisting of CH and N; R1 and R2 are independently selected from the group consisting of NH2, NHR4 and NR52, where R4 and R5 each represent a lower alkyl group, or R1 and R2 together represent a cycle selected from (a), (b) and (c), wherein R6, R7 and R8 are independently selected from the group consisting of hydrogen atoms, lower alkyl groups, hydroxy groups and lower alkoxy groups; and Z is selected from the group consisting of O.

Abstract: The compound referred to herein as IB-962 12, having structure (I) can be obtained by cultivating the strain of Micromonospora sp. ES25-008, available under the accession number CECT-3333, and can be hydrolyzed to give IB-96212B having structure (II). The sugar substituent which is L-rhodinose, can its elf be derivatized or the sugar can be replaced, in either case, giving further derivatives of IB-96212 having a group other than L-rhodinose at the position of the sugar.

Abstract: The present invention discloses new cytotoxic tris(oxazole)-containing macrolides having the formula: wherein X represents a lower alkyl; R1 and R2 represent hydrogen or lower alkyl; R3a represents hydrogen, and R3b represents or R3a and R3b together represent oxygen; R4 represents hydrogen, lower alkoxy or lower alkyl; R5 represents hydrogen, carbamoyl, or lower alkanoyl; R6a represents hydrogen, and R6b represents hydroxy, or R6a and R6b together represent oxygen; R7 represents hydrogen, lower alkyl, or hydroxymethyl; R8 represents lower alkoxy or lower alkyl; Y1 represents hydrogen or methyl, and y2 represents hydrogen, or Y1 and Y2 together represent a double bond. Also disclose are methods for treating mammals using the macrolides and pharmaceutical preparations including the macrolides.

Abstract: The lamellarin compounds disclosed herein have been found to be inhibitors of MDR, i.e., acquired multidrug resistance, which has become a major problem in the treatment of various cancers. The lamellarin compounds disclosed herein have also been found to be cytotoxic to MDR cells. MDR is believed to be associated with certain alterations in tumor cells, including an over-expression of a certain high molecular weight membrane glycoprotein and a decrease in the ability of the tumor cell to accumulate and retain chemotherapeutic agents. The present invention is thus directed to methods of treating MDR-type tumors with an effective anti-MDR amount (either inhibitory or cytotoxic) of one or more lamellarin compounds, which compounds have been found to be effective antitumoral agents against MDR cells.

Abstract: The lamellarin compounds disclosed herein have been found to be inhibitors of MDR, i.e., acquired multidrug resistance, which has become a major problem in the treatment of various cancers. The lamellarin compounds disclosed herein have also been found to be cytotoxic to MDR cells. MDR is believed to be associated with certain alterations in tumor cells, including an over-expression of a certain high molecular weight membrane glycoprotein and a decrease in the ability of the tumor cell to accumulate and retain chemotherapeutic agents. The present invention is thus directed to methods of treating MDR-type tumors with an effective anti-MDR amount (either inhibitory or cytotoxic) of one or more lamellarin compounds, which compounds have been found to be effective antitumoral agents against MDR cells.