-- Subject the sample to complete acetylation using acetic anhydride to give crystals of trichloro pentaacetate (TGSPA), which then undergoes alcoholysis using CH3OH/CH3ONa as a catalyst to remove the three acetyl groups.

（请教化学专家。。。）

For your reference:


紙業在線——PAPEREC - [ Translate this page ][ 簡體 ]acetyl vanilloyl, [乙酰基香草酰]. acetylate, [乙酰化，乙酰化產物]. acetylation, [乙酰化（作用）]. achromatic, [消色的，消色差的] ...
219.156.123.3/paper/dict/list.asp?page=5&key=a - 21k - Cached - Similar pages

阿斯匹靈阿斯匹靈( aspirin )，C9H8O4，學名：乙醯水楊酸(acetyl salic ylic acid)，為無色 ... 阿斯匹靈通常由水楊酸( salicylic acid，柳酸)和乙酸酐( acetic anhydride，醋 ...
general.chemistry.pu.edu.tw/aspirin/aspirin.htm - 12k - Cached - Similar pages

酯化反應酯化反應亦是一個酸與鹽基的中和反應... 亦可採用過量的酸與醇來發生反應). 反應類別:. 1.氯化醯的醇解(Alcoholysis of acid chloride). 2. 酸酐類的醇解(Alcoholysis of acid anhydrides) ...
general.chemistry.pu.edu.tw/ester/esterification.htm - 9k - Cached - Similar pages

The acetylation of apiitol in the determination of apiose.The complete acetylation of apiitol required 9 h when acetic anhydride at 120 degrees was used and s...
www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve& db=PubMed&list_uids=2379200&dopt=Abstract - Similar pages


Acetylation products of pentacyclic triterpene glucosides from ...
In order to achieve complete acetylation including that of sterically ... Acetylation using acetic anhydride and DMAP at room temperature for 48 hours also ...
www.arkat-usa.org/ark/journal/ 2003/I04_Hoornaert/GH-552G/552G.asp - 101k - Cached - Similar pages




http://freepatentsonline.com/4380476.html
However, it is a preferred feature of the process of the present invention, that the chlorinated material is isolated after first being peracylated. Thus, for example, the trichloro-monoacetate intermediate is preferably fully acetylated in situ by reaction with acetic anhydride in pyridine to give the trichloro pentaacetate (TGSPA). This material can then be extracted from an aqueous work-up system, using a solvent such as ethyl acetate or toluene, crystallised, and de-esterified.


--------------------------------------------------
Note added at 1 hr (2006-04-01 15:44:39 GMT)
--------------------------------------------------

... to remove three acetyl groups from the TGSPA.

--------------------------------------------------
Note added at 4 hrs (2006-04-01 18:51:26 GMT)
--------------------------------------------------

you may drop "the" from "remove the three acetyl groups" in the original suggestion... that's actually a better way to say it than the second suggestion...

--------------------------------------------------
Note added at 4 hrs (2006-04-01 18:53:33 GMT)
--------------------------------------------------

"give" can be replaced by "produce"...