“…Therefore, the chirality of C‐3′ was R . Thus, the structure of 1 was established with its absolute configuration, which is an asymmetric diastereomer (at position 11′) of 2 (Xu et al reported other three asymmetric diastereomers of 2 recently [at positions 2, 11, 2′, 3′, and 11′ for “compound 1 ”, at positions 2, 11, 2′, 3′, 11′, and 15′ for “compound 2 ”, and at positions 2, 11, 2′, 3′, 11′, and 15 for “compound 3”]). All the remaining ROESY correlations were consistent with this structure (Figure a).…”