1)  3-epi-betulinic acid
3-表白桦脂酸
1.
Based on the physical and spectroscopic data, they were identified as β-sitosterol, 3-epi-betulinic acid and 3-epi-betulinic acid acetate and the last one was a new natural product.
)茎皮的乙醚提取液中分离到3个脂溶性化合物,经光谱数据分析分别鉴定为β-谷甾醇[I〕(β-sitosterol)、3-表白桦脂酸〔Ⅱ〕(3-ePi-betulinic acid)和3-表白桦脂酸乙酸酯[Ⅲ〕(3-epi-betulinic acid acetate),均为首次从该属植物中获得,其中[Ⅲ)为一新的天然产物。
2)  3-epi-betulinic acid acetate
3-表白桦脂酸乙酸酯
1.
Based on the physical and spectroscopic data, they were identified as β-sitosterol, 3-epi-betulinic acid and 3-epi-betulinic acid acetate and the last one was a new natural product.
)茎皮的乙醚提取液中分离到3个脂溶性化合物,经光谱数据分析分别鉴定为β-谷甾醇[I〕(β-sitosterol)、3-表白桦脂酸〔Ⅱ〕(3-ePi-betulinic acid)和3-表白桦脂酸乙酸酯[Ⅲ〕(3-epi-betulinic acid acetate),均为首次从该属植物中获得,其中[Ⅲ)为一新的天然产物。
3)  NO_3~-
NO~3~-
4)  NO~-_3
NO~-_3
5)  As~(3+)
As~（3+）
6)  3×3×3 lemma
3×3×3引理
1.
This article extends snake lemma to two snakes lermma,and entends 3×3 lemma to 3×n lemma 3×3×3 lemma,Moreover,it studies some problems on exact plane,exact cube as well as problems on cubic commtative diagrams.
将蛇引理推广到双蛇引理,将3×3引理推广到3×n引理、3×3×3引理,并研究了与正合平面、正合立体有关的几个问题及立体交换图问题。
参考词条
补充资料：白桦脂酸
分子式：C30H48O3
分子量：456.71
CAS号：472-15-1

性质：熔点295-298°C (dec.)。

说明：补充资料仅用于学习参考，请勿用于其它任何用途。