Synthesis of Novel Heterocycle Systems: 6,8-Dimethyl-2-(Methylsulfanyl)-4-Amino-Substituted Pyrimido[4′,5′:3,4]Pyrazolo[1,5-a]Pyrimidine and 9,11-Dimethyl-5-(Methylsulfanyl)Pyrimido[2′,1′:5,1]Pyrazolo[4,3-e][1,2,4] Triazolo[4,3-c]Pyrimidine