Heljo Kangur Protopapa

2,4-Diaminopyrimidines from Dicyandiamide. III. Reaction with Monocyclic Ketones^*,1-4

Edward J. Modest, Suprabhat Chatterjee, Heljo Kangur Protopapa · The Journal of Organic Chemistry · 1965 · 20 citations

Natural Sciences, Chemistry, Medicinal Chemistry +8

2,4-Diaminopyrimidines from dicyandiamide. IV. Condensation with bicyclic aromatic ketones

S. K. Sengupta, Suprabhat Chatterjee, Heljo Kangur Protopapa et al. · The Journal of Organic Chemistry · 1972 · 19 citations

Natural Sciences, Chemistry, Medicinal Chemistry +11

Pyrimidine Derivatives. VI. 2,4,5-Triamino-6-chloro- and -6-mercaptopyrimidine and Related Compounds^1,2

Mervyn Israel, Heljo Kangur Protopapa, Herbert N. Schlein et al. · Journal of Medicinal Chemistry · 1964 · 14 citations

Natural Sciences, Chemistry, Medicinal Chemistry +8

Quinazolines. I. Formation of a Guanidinoquinazoline during the Three-Component Synthesis of a 4,6-Diamino-1-aryl-1,2-dihydro-s-triazine¹

A. Rosowsky, Heljo Kangur Protopapa, Paul J. Burke et al. · The Journal of Organic Chemistry · 1964 · 12 citations

Natural Sciences, Chemistry, Medicinal Chemistry +7

Pyrimidine Derivatives VII

Mervyn Israel, Heljo Kangur Protopapa, Suprabhat Chatterjee et al. · Journal of Pharmaceutical Sciences · 1965 · 12 citations