[有機] Fischer's Proof of D-Glucose

看板LifeSci_100作者yutsao (一包)時間12年前 (2012/06/07 12:04)推噓7(7推 0噓 1→)

留言8則, 8人參與討論串1/1

下課不少同學來問我這個部分，打個（或許）比較好懂的整理給大家。期末考加油。 Part I. Reactions used in Fischer's proof 1. Nitric acid oxidation CHO COOH | HNO3 | (CHOH)n --------> (CHOH)n | | CH2OH COOH aldose aldonic acid 2. Kiliani-Fischer synthesis CN CN CHO | | | HCN H-C-OH HO-C-H (CHOH)N --------> | + | | (CHOH)n (CHOH)n CH2OH | | CH2OH CH2OH 3. Ruff degradation CHO | CHO CHOH ------> | | ------> (CHOH)n + CO2 (CHOH)n | | CH2OH CH2OH ============================================================================== Part II. Fischer's proof of the configuration of D-(+)-glucose 1. It's a D-sugar, so there are 8 (= 2^3) possibilities: 1 2 3 4 5 6 7 8 CHO CHO CHO CHO CHO CHO CHO CHO | | | | | | | | H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H | | | | | | | | H-C-OH H-C-OH HO-C-H HO-C-H H-C-OH H-C-OH HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH HO-C-H HO-C-H HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH | | | | | | | | CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH 2. After adding HNO3, it should be an optically active compound. X X 1 2 3 4 5 6 7 8 CHO CHO CHO CHO CHO CHO CHO CHO | | | | | | | | H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H | | | | | | | | H-C-OH H-C-OH HO-C-H HO-C-H H-C-OH H-C-OH HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH HO-C-H HO-C-H HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH | | | | | | | | CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH 3. We get an optically active acid after degradation followed by HNO3 X X X X X 1 2 3 4 5 6 7 8 CHO CHO CHO CHO CHO CHO CHO CHO | | | | | | | | H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H H-C-OH HO-C-H | | | | | | | | H-C-OH H-C-OH HO-C-H HO-C-H H-C-OH H-C-OH HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH HO-C-H HO-C-H HO-C-H HO-C-H | | | | | | | | H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH H-C-OH | | | | | | | | CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH CH2OH HCN 4. (-)-Arabinose -----> Glucose + Mannose No.3 and No.4 might be glucose and mannose. or No.7 and No.8 might be glucose and mannose HNO3 5. Glucose + Mannose ------> Both are optically active HNO3 No.7 ------> Optically inactive So No.3 and No.4 are glucose and mannose 6. L-glucose + HNO3 ------> Glucaric acid ┐ ├ The same D-glucose + HNO3 ------> Glucaric acid ┘ It turns out that No.3 is glucose and No.4 is mannose. -- ※ 發信站: 批踢踢兔(ptt2.cc) ◆ From: 140.112.4.201 ※ 編輯: yutsao 來自: 140.112.4.201 (06/07 12:05)

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