作為革蘭氏陰性菌外膜主要的組成成分，脫氧的鼠李糖耦合物在細胞跟細胞間的辨識扮演著關鍵的角色。在此由商品化的鼠李糖和神經鞘胺醇經由16步合成出胺基醣酯質類似物(2S,3R,4S,5R,6R)-2-((2R, 3R,4R,5S,6S)-2-((2S,3S,4R)-2-amino-3,4-dihydroxyoctadecyloxy)-3,5-dihydroxy-6-methyltetrahydro-2H-pyran-4-yloxy)-6-(aminomethyl)tetrahydro-2H-pyran-3,4,5-triol總產率5%，並且其中有兩個主要的中間產物，分別為(2R,4S,5S,6S)-2-(azidomethyl)-6-((2S,3S,4R,5R,6S)-3-(benzoyl oxy)-5-(4-methoxybenzoyloxy)-2-methyl-6-(p-tolylthio)tetrahydro-2H-pyran-4-yloxy)tetrahydro- 2H-pyran-3,4,5-triyl tribenzoate (產率：17%，起始物為鼠李糖)和(2S,3S,4R)-2-azido-1-hydroxyoctadecane-3,4-diyl dibenzoate (產率：44%起始物為神經鞘胺醇)。在此目的為製備出可用於分子影像的放射性標幟之醣酯質，放射性氟十八標幟之鼠李糖和神經醯胺耦合分子為目標化合物，製備氟十八標幟醣酯質的前驅物例如tosylate，(2R,3R,4R,6S)-2-((2S,3S,4R)-2-azido-3,4-bis(tert-butyldimethyl silyloxy)octadecyloxy)-5-(benzoyloxy)-4-(2-chloroacetoxy)-6-methyltetrahydro-2H-pyran-3-yl 4-methoxybenzoate可以從鼠李糖經由11步合成並且總產率13%。

As a major component of outer layer of gram-negative bacteria, glycoconjugate of L-rhamnose plays a crucial role in mediating cell-cell recognition. The desired glycoceramide analog (2S,3R,4S,5R,6R)-2-((2R, 3R,4R,5S,6S)-2-((2S,3S,4R)-2-amino-3,4-dihydroxyoctadecyloxy)-3,5-dihydroxy-6-methyltetrahydro-2H-pyran-4-yloxy)-6-(aminomethyl)tetrahydro-2H-pyran-3,4,5-triol was prepared from commercial L-rhamnose and phytosphingosine via intermediate: (2R,4S,5S,6S)-2-(azidomethyl)-6- ((2S,3S,4R,5R,6S)-3-(benzoyloxy)-5-(4-methoxybenzoyloxy)-2-methyl-6-(p-tolylthio)tetrahydro-2H-pyran-4-yloxy)tetrahydro-2H-pyran-3,4,5-triyl tribenzoate (yield : 17% base on rhamnose) and intermediate: (2S,3S,4R)- 2-azido-1-hydroxyoctadecane-3,4-diyldibenzoate (yield : 44% base on phytosphingosine) in a total yield of 5%. Radiolabeled glycoceramides were attempted to be prepared for imiaging purpose. Rhamnosyl phytosphingosine labeled with 18F emerged as our target compound. The precursor to 18F rhamnosyl phytosphingosine analogs e.g. a tosylate was thus prepared. An alcohol required for tosylate preparation, (2R,3R,4R, 6S)-2-((2S,3S,4R)-2-azido-3,4-bis(tert-butyldimethylsilyloxy)octa decyloxy)-5-(benzoyloxy)-4-(2-chloroacetoxy)-6-methyltetrahydro-2H- pyran-3-yl 4-methoxybenzoate, was obtained via a 11-step synthesis starting from rhamnose in total 13% yield.

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