Abstract: Compounds useful as anti-allergic agents are 2-Q-4-[XZC=C(R)NH]-5-R.sub.1 -6-R.sub.2 -pyrimidines (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen, lower-alkyl, hydroxy or halo, X and Z are the same or different and are each selected from lower-carbalkoxy, lower-alkanoyl, carbamyl and cyano, or ##STR1## is ##STR2## where R.sub.3 and R.sub.4 are each lower-alkyl, or X is hydrogen, are prepared by reacting 4-amino-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidine (II where Q' is amino) with R'O--C(R)=CXZ (III). Preparations of II are given. Also shown as intermediates and/or anti-allergic agents are 4-(AcNH)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (IV) and 4-(R.sub.5 R.sub.6 N)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (V) where Ac is lower-alkanoyl or lower-carbalkoxy, R.sub.5 is hydrogen, lower-alkyl or lower-hydroxyalkyl, and R.sub.

Abstract: Compounds useful as anti-allergic agents are 2-Q-4-[XZC=C(R)NH]-5-R.sub.1 -6-R.sub.2 -pyrimidines (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen, lower-alkyl, hydroxy or halo, X and Z are the same or different and are each selected from lower-carbalkoxy, lower-alkanoyl, carbamyl and cyano, or ##STR1## where R.sub.3 and R.sub.4 are each lower-alkyl, or X is hydrogen, are prepared by reacting 4-amino-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidine (II where Q' is amino) with R'O-C-(R)=CXZ (III). Preparations of II are given. Also shown as intermediates and/or anti-allergic agents are 4-(AcNH)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (IV) and 4-(R.sub.5 R.sub.6 N)-2-Q-5-R.sub.1 -6-R.sub.2 -pyrimidines (V) where Ac is lower-alkanoyl or lower-carbalkoxy, R.sub.5 is hydrogen, lower-alkyl or lower-hydroxyalkyl, and R.sub.

Abstract: Compounds useful as anti-allergic agents are N-R.sub.3 -N-R.sub.4 -N'-R-N'-(2-Q-5-R.sub.1 -6-R.sub.2 -4-pyrimidinyl)ureas (I), where Q is 4- or 3- or 2-pyridinyl or 4- or 3- or 2-pyridinyl having one or two lower-alkyl substituents or N-oxide thereof, R is hydrogen or lower-alkyl, R.sub.1 is hydrogen, lower-alkyl or cyano, R.sub.2 is hydrogen or lower-alkyl, R.sub.3 is hydrogen, lower-alkyl or lower-hydroxyalkyl, R.sub.4 is hydrogen, lower-alkyl, lower-hydroxyalkyl, lower-alkenyl or lower-cycloalkyl. Said ureas are prepared by reacting 2-Q-4-RNH-5-R.sub.1 -6-R.sub.2 -pyrimidine (II) with a carbamylating agent selected from an R.sub.4 '-isocyanate of the formula R.sub.4 'N=C=O to produce N-R.sub.4 '-N'-R-N'-(2-Q-5-R.sub.1 -6-R.sub.2 -4-pyrimidinyl)urea (IA), an N-R.sub.3 '-N-R.sub.4 '-carbamyl halide of the formula R.sub.3 'R.sub.4 'NC(=O)-halide to produce N-R.sub.3 '-N-R.sub.4 'N'-R-N'-(2-Q-5-R.sub.1 -6-R.sub.2 -4-pyrimidinyl)urea (IB) or 1,1'-carbonyldiimidazole to produce N-(2-Q-5-R.sub.1 -6-R.sub.

Abstract: Antibacterial 5,8-dihydro-8-(lower-alkyl)-5-oxo-2-Q-4-R.sub.2 -6-Z-pyrido[2,3-d]pyrimidine (I) where Z is carboxy or lower-carbalkoxy, R.sub.2 is hydrogen or lower-alkyl and Q is 4(or 3)-pyridinyl or 4(or 3)-pyridinyl having one or two lower-alkyl substituents is prepared by heating di-(lower-alkyl) N-(2-Q-6-R.sub.2 -4-pyrimidinyl)aminomethylenemalonate (III) to produce 5,8-dihydro-5-oxo-2-Q-4-R.sub.2 -6-Z-pyrido[2,3-d]pyrimidine (II) which is tautomeric with 5-hydroxy-2-Q-4-R.sub.2 -6-Z-pyrido[2,3-d]pyrimidine (IIA) where Q and R.sub.2 are the same as in I above and Z is lower-carbalkoxy, reacting II(or IIA) with a lower-alkylating agent to produce I where Z is lower-carbalkoxy and hydrolyzing this ester (I) to produce I where Z is carboxy. Alternatively, the acid (II or IIA where Z is COOH) can be alkylated after first hydrolyzing the ester (II or IIA where Z is lower-carbalkoxy). The preparations of the intermediate III and intermediates used in its preparation are given.