Using a wedge-type cubic anvil high pressure apparatus, metal-IVA and -VA group compounds have systematically been prepared at high temperatures and high pressures. In this paper we mainly report the electrical properties of the compounds with skutterudite (CoAs
3-type) structure prepared at high pressure. CoP
3 and CeRu
4P
12 behave as a semiconductor. NiP
3 is a metal. LaRu
4P
12 is a superconductor with T
c of 7 K. The electrical resistivity of alloys La
1-xCe
xRu
4P
12 rapidly increases with increasing x. The metal to semiconductor transition is observed at around X=0. 6. PrRu
4P
12 shows the electrical anomaly due to the metal-insulator transition at around 60 K. The T
c's of new superconductors LaRu
4As
12 and LaRu
4Sb
12 are 10. 3 K and 2. 8 K, respectively. LaRu
4As
12 has the highest T
c in the skutterudite compounds. PrRu
4As
12 is an interesting superconductor containing the magnetic rare earth with T
c of 2. 5 K though PrRu
4P
12 behaves as the semiconductor below 60 K. We have found the new compound superconductors, ZrRuSi, ZrRuGe, ZrRu
4P
12, LaRu
4As
12 and ZrRhSi, with T
c of above 10 K in metal-IVA and -VA group compounds prepared at high pressure.
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