Warfarin is found in sweet clovers. Its story is really fascinating; I recommend having a look at this video on the topic [1]. For hardcore people who're into pharm, the story is also reported on Goodman & Gilman. [1]https://tube.cadence.moe/watch?v=OnzF0oJkYe0
Codeine is the prodrug of morphine, which in turn is a opiate. I bet you know where it comes from.
Vincristine (a chemotherapic), like other alkaloids with antiblastic/cytostatic properties, is derived from 'vinca rosacea', commonly referred to as 'bright eye' (pic below).
As my aunt always reminds me, that should be "warfarin (rat poison)".
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@publius very good catch on the rat poison. However, how many poisonous herbs can you count? Surprise :-)
https://tube.cadence.moe/watch?v=OnzF0oJkYe0
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People routinely eat poisonous herbs. Fennel is a great example.
But when my grandfather was in his 90s and taking Warfarin, every time my aunt saw the pill bottle, she would say (referring to her days in the Peace Corps), "that's what we used to kill rats in Kenya!"
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@publius great story!!
Penicillin is indeed the only in the group not to be plant-based. It comes from a mould (fungus) with antibacterial propertis, as observed by Fleming in the distant 1928. https://en.m.wikipedia.org/wiki/Penicillium