Abstract: 1,2-dihydropyrido[3,4-b]pyrazines are provided which possess antimitotic activity. The compounds have the structure: ##STR1## wherein R is a lower alkyl group and OR.sub.1 is a member selected from the group consisting of aryl-alkyl ethers having from seven to about 20 carbon atoms, alkyl carbamates having from one to about 12 carbon atoms, the alkyl portion of which may be substituted with a halogen atom, e.g., chlorine, fluorine, bromine or iodine; aryl-alkyl carbamates having from about seven to about 20 carbon atoms, aryl carbamates having from about six to about 20 carbon atoms, aryl-alkyl esters having from about 7 to about 20 carbon atoms, aryl esters having from about six to about 20 carbon atoms, alkylthiocarbamates having from about one to about 12 carbon atoms, aryl-alkylthiocarbamates having from about seven to about 20 carbon atoms, and arylthiocarbamates having from about six to about 20 carbon atoms.

Abstract: The (2S)-(-)-isomer of (5-amino-1,2-dihydro-2-methyl-3-phenylpyrido[3,4-b]pyrazin-7-yl)carbamic acid, ethyl ester is significantly more potent than either the (2R)-(+)-isomer or the (R,S)-(.+-.)-racemic mixture in inhibiting mitotic cell division of L1210 leukemia cells.The compound, pharmaceutical compositions containing the compound, and a method of ameliorating cancer diseases in mammals are disclosed.

Abstract: It is disclosed that a compound having the formula ##STR1## or a pharmaceutically acceptable salt thereof in combination with vincristine produces synergistic antitumor activity.

Abstract: The (2S)-(-)-isomer of (5-amino-1,2-dihydro-2-methyl-3-phenylpyrido[3,4-b]pyrazin-7-yl)arbamic acid, ethyl ester is significantly more potent than either the (2R)-(+)-isomer or the (R,S)-(.+-.)- racemic mixture in inhibiting mitotic cell division of L1210 leukemia cells.The compound, pharmaceutical compositions containing the compound, and a method of ameliorating cancer diseases in mammals are disclosed.

Abstract: 1,2-Dihydropyrido[3,4-b]pyrazines are provided which possess anticancer activity. The compounds have the structure: ##STR1## wherein Y is CH.sub.2 or N(CH.sub.3); R.sub.1 is a lower alkyl group; e.g., an alkyl group containing up to six carbon atoms such as methyl, ethyl, propyl, butyl, etc.; R.sub.2 is a member selected from the group consisting of hydrogen, CH.sub.3 O or Cl; and R.sub.3 and R.sub.4 are either both hydrogen or one is hydrogen and the other is a lower alkyl group.

Abstract: There are disclosed novel intermediates useful in the preparation of pyrido[2,3-d]pyrimidines having the following structures: ##STR1## wherein R is CH.sub.3, CH.sub.3 CH.sub.2, CH.sub.3 CH.sub.2 CH.sub.2, CH.sub.2 .dbd.CHCH.sub.2 or CH.tbd.CCH.sub.2 ; and ##STR2## wherein R is CH.sub.3, CH.sub.3 CH.sub.2, CH.sub.3 CH.sub.2 CH.sub.2, CH.sub.2 .dbd.CHCH.sub.2 or CH.tbd.CCH.sub.2. These intermediates have the formulas: ##STR3## wherein Y is CHO, CH.sub.2 OH or CH.sub.2 Br; and Z is CH.sub.2 OH or CH.sub.2 Br.

Abstract: 1,2-Dihydropyrido[3,4-b]pyrazines are provided which possess anticancer activity. The compounds have the structure: ##STR1## wherein Y is CH.sub.2 or N(CH.sub.3); R.sub.1 is a lower alkyl group; e.g., an alkyl group containing up to six carbon atoms such as methyl, ethyl, propyl, butyl, etc.; R.sub.2 is a member selected from the group consisting of hydrogen, CH.sub.3 O or Cl; and R.sub.3 and R.sub.4 are either both hydrogen or one is hydrogen and the other is a lower alkyl group.

Abstract: There are disclosed novel intermediates useful in the preparation of pyrido[2,3-d]pyrimidines having the following structure: ##STR1## wherein R is CH.sub.3, CH.sub.3 CH.sub.2, CH.sub.3 CH.sub.2 CH.sub.2, CH.sub.2 .dbd.CHCH.sub.2 or CH.tbd.CCH.sub.2. The intermediate has the formula: ##STR2## wherein Z is CH.sub.2 OH or CH.sub.2 Br.

Abstract: There is disclosed a novel intermediate useful in the preparation of pyrido [2,3-d] pyrimidines, which includes N-[4-[(2-amino-4(3H)-oxopyrido[2,3-d]pyrimidin-6-yl)methylamino]benzoyl]-L -glutamic acid (5-deazafolic acid), N-[4-[[2-amino-4(3H)-oxopyrido[2,3-d]-pyrimidin-6-yl)methyl]methylamino]be nzoyl]-L-glutamic acid (5-deaza-N.sup.10 -methylfolic acid), N-(4-[(2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methylamino]benzoyl]-L-gluta mic acid (5-deazaaminopterin), and N-[4-[[2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methyl]methylamino]benzoyl]- L-glutamic acid (5-deazamethotrexate). This intermediate is the compound 2,4-diamino-6-(hydroxymethyl)pyrido-[2,3-d]pyrimidine.

Abstract: Compounds of the formulas ##STR1## where the substituents are as defined within are disclosed as intermediates to make antifungal 1,2-Dihydropyrido[3,4-b]pyrazines.

Abstract: There are disclosed certain 2H-pyrido[4,3-b][1,4]oxazines and 2H-pyrido[4,3-b][1,4]thiazines which possess biological activity. The compounds have the structure: ##STR1## wherein n has a value of 1,2 or 3; X is oxygen or sulfur; R.sub.1 is a lower alkyl group, e.g., an alkyl group containing up to six carbon atoms such as methyl, ethyl, propyl, butyl, etc.; R.sub.2 is a member selected from the group consisting of hydrogen, alkyl radicals having from about one to about 12 carbon atoms, preferably from about one to about six carbon atoms; alkenyl radicals having from about two to about 15 carbon atoms; preferably from about two to about 10 carbon atoms; cycloalkyl radicals having from about three to about 20 carbon atoms, preferably from about three to about 15 carbon atoms; aryl, aralkyl and alkaryl radicals having from about six to about 20 carbon atoms, preferably from about six to about 15 carbon atoms; a halogen radical, e.g.

Abstract: 1,2-Dihydropyrido[3,4-b]pyrazines are provided which possess antifungal and anticancer activity. The compounds have the structure: ##STR1## wherein x has a value of 1, 2 or 3; R.sub.1 is a lower alkyl group, R.sub.2 is a member selected from the group consisting of hydrogen, alkyl radicals having from about one to about 12 carbon atoms, alkenyl radicals having from about two to about 15 carbon atoms, cycloalkyl radicals having from about three to about 20 carbon atoms, aralkyl and alkaryl radicals having from about six to about 20 carbon atoms, a halogen radical, provided that when x has a value of 1 and R.sub.2 is in the para position and R.sub.3 and R.sub.4 are both hydrogen, R.sub.

Abstract: There is disclosed a novel intermediate useful in the preparation of pyrido[2,3-d]pyrimidines, which includes N-[4- [(2-amino-4(3H)-oxopyrido[2,3-d]pyrimidin-6-yl)methylamino]benzoyl]-L-glut amic acid (5-deazafolic acid), N-[4-[[(2-amino-4(3H)-oxopyrido[2,3-d]-pyrimidin-6-yl)methyl]methylamino]b enzoyl]-L-glutamic acid (5-deaza-N.sup.10 -methylfolic acid), N-[4-[(2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methylamino]benzoyl]-L-gluta mic acid (5-deazaaminopterin), and N-[4-[[(2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methyl]methylamino]benzoyl] -L-glutamic acid (5-deazamethotrexate). This intermediate is the compound 2,4-diaminopyrido[2,3-d]pyrimidine-6-carboxaldehyde.

Abstract: Improved methods for the preparation and purification of citrovorum factor are disclosed. The method includes improved procedures for hydrogenation of 10-formylfolic acid as well as for the reduction of folic acid. Also disclosed are improved procedures for opening of the imidazoline ring, and a non-chromatographic method for the purification of crude samples of citrovorum factor.

Abstract: Improved methods for the preparation and purification of citrovorum factor are disclosed. The method includes improved procedures for hydrogenation of 10-formylfolic acid as well as for the reduction of folic acid. Also disclosed are improved procedures for opening of the imidazoline ring, and a non-chromatographic method for the purification of crude samples of citrovorum factor.