The largest diamond ever found in the U.S., a white gem named the Uncle Sam, was found here in 1924. It was 40.23 carats, which is basically the size of a gumball. And in the 1950s, a woman found a 15.33-carat diamond.
Alkaloids that possess an isoquinoline skeleton are among the most common of all alkaloids. These are derived from a 3,4-dihydroxytyramine (dopamine) precursor that undergoes a Schiff base addition with aldehydes of different origin.At least 4000 compounds of this structural type are known.hese alkaloids are mostly found in the Cactaceae, but in some other families as well. About 130 isoquinoline alkaloids are known. They are derived from a 3,4-dihydroxytyramine (dopamine) precursor and have an isoquinoline skeleton.
Definition of HYDROQUINONE. : a white crystalline strongly reducing phenol C6H6O2 used especially as a photographic developer, as an antioxidant and stabilizer, and in medicine to remove pigmentation from hyperpigmented areas of skin. ADVERTISEMENT. a white crystalline strongly reducing phenol C6H6O2 used especially as a photographic developer, as an antioxidant and stabilizer, and in medicine to remove pigmentation from hyperpigmented areas of skin. ADVERTISEMENT.