Apparently there is an interaction between soy and thyroxine. This is evidence-based, as studies have demonstrated it. The soy decreases the effect of the thyroxine, making it necessary to take more.
Here is a link that describes the studies on this:
As for the interaction of thyroxine and other supplements, there's a German version of the PDR that covers drugs and their interaction with herbs. Give me a moment or so and I'll search this as well to see what I can find for you.
Here's a link from the University of Michigan outlining the effects of various herbs and showing how they could interact with drugs:
It doesn't look as though thyroxine reacts with the herbs you mentioned specifically, but still I would monitor their use carefully and listen to my own body.
I hope this has been helpful to you.
Here is another site in which a clinical study is discussed:
Apparently, gingko biloba does thin the blood and therefore must be used with great caution with NSAIDS, aspirin or drugs like coumadin or lovenox.
I will check specifically for Coq 10 and red clover and see what I can come up with.
Here is another link from University of Maryland Medical Center regarding the potential drug interactions with coq10:
Apparently, this drug may enable some people to reduce their dose of BP medication. It can also reduce the toxic effects of chemotherapy in cancer.
And here is the PDR summary of the interaction between red clover and medications:
Red clover must also be used with caution with blood thinners.
I hope this has been helpful to you and good luck.