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Yes, here Nitrogen has to be considered as a stereocenter. Also, you can assign R and S to it. The rule is that the lone pair has the least priority and then you can assign R and S as you do for other molecules.


Interesting that the cost in the US for the USDA-approved form is US$900 per 1.5 ml IV ampule. (Specific gravity is given as ~1, i.e. 1.5 g per ampule). That chemical, 4-methylpyrazole, "For Research Use Only. Not Intended for Diagnostic or Therapeutic Use.", is available for US$74 per g . So if standard use is 1.5 ml, then the research-grade ...


Answer here from a quality manager in the pharmaceutical field in Europe. Pharmaceutical companies are obliged to perform stability tests for their products according to the relevant pharmaceutical (GMP) agency in your market (FDA/EMA/etc) and the international agreed guidelines like ICH Q1A-F and the WHO). These tests are carried out in stability chambers ...


Avoiding cooling again after keeping it ( for non critical products ) at room temperature is mainly to prevent forgetting it was not cold all the time and that it may will not last as long as expected. Taking food from the fridge, you may not remember after a week or two that it was outside longer than it should be. It can violate the safety by growth of ...

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