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Lifting problem for universal quadratic forms asks for totally real number fields K$K$ that admit a positive definite quadratic form with coefficients in Z$\mathbb {Z}$ that is universal over the ring of integers of K$K$. In this paper, we show K=Q(ζ7+ζ7−1)$K=\mathbb {Q}(\zeta _7+\zeta _7^{-1})$ is the only such totally real cubic field. Moreover, we show that there is no such biquadratic field. [ABSTRACT FROM AUTHOR]

2-Amino-substituted 1,3,4-oxadiazole (II) and 1,3,4-thiadiazole derivatives (V) are prepared from the same thiosemicarbazides (I) depending on the reagents used (EDC or TosCl/NEt3). [ABSTRACT FROM AUTHOR]