Why are the lupanine derivatives bitter ?

为白金雀儿碱的派生物是苦的？

He is bitter in his condemnation of terrorism.

他言辞激烈地谴责恐怖主义。

He liked the bitter taste of the ale.

他喜欢麦芽酒的苦味。

He gave Helen a look of bitter reproach.

他责怪地冷冷看了海伦一眼。

They were all sympathetically disposed towards her bitter experience.

他们都对她的悲惨遭遇寄予同情。

I felt the sting of the cold, bitter air.

我感到寒风刺骨。

St Ambrose would weep bitter tears when confessing a sinner.

圣安布罗斯聆听罪人忏悔时，会流下悲苦的泪水。

But some bitter substances in it such as elaterin are unacceptable.

由于苦瓜含有苦瓜素等物质,苦味较重,令一些消费者难以接受。

Everything new comes from the forge of hard and bitter struggle.

一切新的东西都是从艰苦斗争中炼出来的。

The two countries fell out in a bitter wrangle over imports.

这两个国家有关进口问题的激烈争吵中闹翻了。

Thy wit is a very bitter sweeting; it is a most sharp sauce.

你的笑话又甜又辣；简直是辣酱油。

His visit churned up bitter memories.

他的来访激起了痛苦的回忆。

It tastes bitter.

这东西吃起来很苦。

Quinine has a bitter taste.

奎宁有苦味。

This is a novel depicting the bitter sufferings of the inmates in a Nazi concentration camp.

这是一本描写关押纳粹集中营的人受苦受难的小说。

Sour, sweet, bitter, spiciness and fishiness numb our taste bud so that we cannot taste the light sweet.

酸、甜、苦、辣、腥等麻木我们的口味、舌蕾，再也品尝不出清淡的香甜。

The tannin makes this grape very suitable for ripening on oak barrels.This makes the bitter tannin souple and soft.

单宁是这种葡萄酿制的酒非常橡木桶中成熟， 这可以使单宁的苦涩感变的更柔顺，圆润。

At the age of 40, King Gillette was a frustrated inventor, a bitter anticapitalist, and a salesman of cork-lined bottle caps.

40岁时，金·吉列不过一失意发明人，激烈的反资本主义者，软木衬瓶盖推销员。

This paper has studied the phthalocyanin complex of Cobalt synthesized by benzene bitter wine-urea law,and after depuration,an infrared, ultra-violet spectrograph determination is carried.

文章主要研究了苯酐-尿素法成酞菁钴、经提纯并对其进行红外、紫外光谱测定、成及表征结果表明,红外光谱表征推测结构可靠,紫外光谱分析表明有特征吸收峰之处。

Modern medicine studies: The bitter ginseng in thinking suffering is joined commonly is alkaline reach furzy alkaline have fight rhythm of the heart wrong action.

一般认为苦参中的苦参碱及金雀花碱具有抗心律失常作用。