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3

It is interesting that the very first modern reference to urolithin and its identification is in 1963 in the article cited as Two constituents of clover stone, a type of urinary calculus found in sheep by Nittle, M. C.; Pope, G. S., in Biochemical Journal, 89(1), pg 67 is wrong even in SciFinder and in Google Scholar. If we check the journal website, there ...


3

Actually, most of linear imines and exocyclic imines display $E/Z$-isomerism (commonly known as $cis/trans$-isomerism) with a lone pair on the nitrogen, which is a part of the double bond. The isomerism follows various mechanisms. For instances, $cis/trans$-isomerism of azobenzene a noted elsewhere is operated by UV/vis-irradiation is a good example. The ...


5

OP's request: I am curious as to how it (urolithin) was discovered but cannot find the story. 3,8-Dihydroxybenzo[c]chromen-6-one or 3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one (CAS #: 1143-70-0), now known as urolithin-A is first discovered as a metabolite of ellagic acid from mice in 2003 (Ref.1) by the same research group who also discovered that in as a ...


7

The identification of urolithins as products of human metabolism of ellagic acid was reported by Cerda et al. in the European Journal of Nutrition in 2004. The full reference is Cerda, B., Espin, J.C., Parra, S., Martinez, P. and Tomas-Barberan, F.A. (2004) The potent in vitro antioxidant ellagitannins from pomegranate juice are metabolised into bioavailable ...


5

As @Zhe says, the name urolithin A seems to have derived from the word urolith which is basically kidney stone. Quoting from here1: The name urolithin was first given to two metabolites isolated from the renal calculus of sheep (Trifolium subterraneum has been reported as the cause of clover stone and might be a relevant source of ellagitannins) that were ...


3

Yes. Azobenzene displays cis-trans isomerism. The two isomers can be interconverted using UV/Visible-irradiation. The less stable cis-isomer will relax back to the more stable trans-isomer, but the lifetime of the cis-isomer is long enough to allow observation and characterization.


0

This is not true. There are more isotopes that had (and have now) its own name. For example: 210Po - RaF (Radium F); 218Po - RaA (Radium A); 218Pb - RaB; 227Th - RdAc (Radioactinium); and much more Some of the names are still widely used (f.e. RaF)


2

You're right, the two compounds you depicted are basically the same molecule except for in their chirality. They are, essentially, enantiomers of each other. In the slightly clearer depiction below, by the Cahn-Ingold-Prelog convention we would call the molecule on the left S-bromochlorofluoromethane, while the one on the right would be its R-enantiomer, i....


-2

The double bond has to have a priority here so both carbons get first and second position. The double bonded carbon with methyl group will get first position. In this way, we are forced to go clockwise. Thus, the name is 1,5,6-trimethylcyclohex-1-ene.


1

1,5,6-trimethylcyclohex-1-ene The double bond is the functional group in the molecule, so this wants to be between the lowest two numbers which means we number clockwise around the ring. Resulting in the methyl group taking positions 1,5,6.


2

"$\ce{KNaSO4}$" is correct, but not because of electronegativity order, but rather the alphabetical one. From IUPAC "Red Book", section IR-2.15 ORDERING PRINCIPLES [1, p. 40]: IR-2.15.2 Alphabetical order Alphabetical order is used in formulae as follows. (a) Within the group of cations and within the group of anions, respectively, in ...


6

As suggested in the comments, the predecessor of the method that uses "Missouri" tablets was developed at the University of Missouri (Columbia, Missouri, USA). I believe the first report was from 1972 and named the method as the "Missouri Automated Nitrogen Method (MANM)". They also refer to it as the "Missouri Technicon" method ...


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