Answer:
Four possible isomers (1–4) for the natural product essramycin. The structure of compound 1 was attributed to essramycin by 1H NMR, 13C NMR, HMBC, HRMS, and IR experiments.
Explanation:
Three synthetic routes were used to prepare all four compounds (Figure 2A). All three reactions utilize 2-(5-amino-4H-1,2,4-triazol-3-yl)-1-phenylethanone (5) as the precursor, whereas each uses different esters (6–8) to construct the pyrimidinone ring. Isomer 1 was prepared by reaction A, which used triazole 5 and ethyl acetoacetate (6) in acetic acid. This was the reaction used in syntheses of essramycin by the Cooper and Moody laboratories.3,4 Reaction B produced compound 2 (minor product) and compound 3 (major product), which were separated chromatographically. This reaction allowed reagent 5 to react with ethyl 3-ethoxy-2-butenoate (7) in the presence of sodium in methanol, under reflux for 24 h. Compound 4 was prepared by reaction C, which was obtained by reflux of 5 and methyl 2-butynoate (8) in n-butanol.
Answer:
he major types of connective tissue are connective tissue proper, supportive tissue, and fluid tissue. Loose connective tissue proper includes adipose tissue, areolar tissue, and reticular tissue.
Explanation:
Answer:
285.185 (.185 repeating) cm^3
Explanation:
To get the answer, you divide 140 by 27 to get 5.185 (.185 repeating). Then, you multiply 5.185 (.185 repeating) by 55 and get 285.185 (.185 repeating) cm^3. Please use ^ next time to indicate exponents.
Answer:
The proton remains the same.
Explanation:
Oxidation is simply defined as the loss of electron(s) during a chemical reaction either by an atom, molecule or ion.
Oxidation is strictly on the transfer of electron(s) and not proton.
A metal that undergoes oxidation still has its protons intact otherwise it will not be called the ion of the metal since atomic number is called the proton number.
Sodium (Na) undergoes oxidation as follow:
Na —> Na+ + e-
Na is called sodium metal.
Na+ is called sodium ion.
Na has 11 electrons and 11 protons
Na+ has 10 electrons and 11 protons
From the above illustration, we can see that the protons of Na and Na+ are the same why their electrons differ because Na+ indicates that 1 electron has been loss or transferred.
