DOCSLIB.ORG

WO 2007/132990 Al

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
WO 2007/132990 Al (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (43) International Publication Date (10) International Publication Number 22 November 2007 (22.11.2007) PCT WO 2007/132990 Al (51) International Patent Classification: (74) Agents: KIM, Jin-Hak et al; # 1106, Kumsan Bldg., 17-1 C07D 405/06 (2006.01) Youido-dong, Youngdeungpo-ku, Seoul 150-727 (KR). (21) International Application Number: (81) Designated States (unless otherwise indicated, for every PCT/KR2007/002154 kind of national protection available): AE, AG, AL, AM, AT,AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, CA, CH, (22) International Filing Date: 2 May 2007 (02.05.2007) CN, CO, CR, CU, CZ, DE, DK, DM, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, (25) Filing Language: English IS, JP, KE, KG, KM, KN, KP, KZ, LA, LC, LK, LR, LS, LT, LU, LY,MA, MD, MG, MK, MN, MW, MX, MY, MZ, (26) Publication Language: English NA, NG, NI, NO, NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, SV, SY, TJ, TM, TN, TR, (30) Priority Data: TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW 10-2006-0042433 11 May 2006 (11.05.2006) KR (71) Applicant (for all designated States except US): RSTECH (84) Designated States (unless otherwise indicated, for every CORPORATION [KR/KR]; #306, Venture Town Jangy- kind of regional protection available): ARIPO (BW, GH, oungsilgwan, 1688-5 Sinil-dong, Daeduk-gu, Daejeon GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, 306-230 (KR). ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), European (AT,BE, BG, CH, CY, CZ, DE, DK, EE, ES, FI, (72) Inventors; and FR, GB, GR, HU, IE, IS, IT, LT,LU, LV,MC, MT, NL, PL, (75) Inventors/Applicants (for US only): KANG, Hyun PT, RO, SE, SI, SK, TR), OAPI (BF, BJ, CF, CG, CI, CM, Bin [KR/KR]; #102-201 Daeju Apt., Sipjeong-dong, GA, GN, GQ, GW, ML, MR, NE, SN, TD, TG). Bupyeong-gu, Incheon 403-130 (KR). QUAN, Long Guo [CN/KR]; #304, Venture Town Jangyoungsilgwan, Published: 1688-5 Sinil-dong, Daeduk-ku, Daejeon 306-230 (KR). — with international search report LEE, Jae Kwan [KR/KR]; #6-706 Samsung Apt., 924-3 Dongchun-dong, Yeonsu-ku, Incheon 406-130 (KR). For two-letter codes and other abbreviations, refer to the "G uid KIM, Seong-Jin [KR/KR]; #502, Keangnamhonorsville, ance Notes on Codes and Abbreviations" appearing at the beg in lijok-dong, Yuseong-gu, Deajeon 305-330 (KR). ning of each regular issue of the PCT Gazette. (54) Title: PROCESS FOR THE PREPARATION OF CHIRAL GLYCIDYLPHTHALIMIDE IN HIGHLY OPTICAL PURITY (57) Abstract: The present invention relates to a process for the preparation of highly optical pure glycidylphthalimide. More particularly, the present invention relates to a process for the preparation of chiral glycidylphthalimide, which comprises the steps of reacting an optically active 3-susbstituted l-amino-2-propanol acid addition salt with phthalic anhydride in a presence of a base to obtain yV-(3-substituted-2-hydroxypropyl)phthalimide and subjecting the obtained compound to an epoxide cyclization reaction to prepare the targeted glycidylphthalimide. According to the process, the chirality of the starting material is substantially retained throughout overall procedures. Therefore, the process can prepare the targeted glycidylphthalimide in an optically pure form having 99%ee or higher. And, the reactions are carried out under mild conditions through overall procedures and in a single reaction vessel without any special purification. This increases the yield of the target compound. Description PROCESS FOR THE PREPARATION OF CHIRAL GLY- CIDYLPHTHALIMIDE IN HIGHLY OPTICAL PURITY Technical Field [1] The present invention relates to a process for the preparation of glycidylphthalimide. More particularly, the present invention relates to a process for the preparation of chiral glycidylphthalimide with high optical purity without decrease of the optical purity of the starting material. Background Art [2] Most of recently developed or commercially available medicines are optically active substances. This is attributed to the fact that conventional racemic medicines often cause side effects or exhibit low therapeutic effects. Various efforts are made to develop medicines with high optical purity in a pure stereo-isomeric form in order to increase stability and therapeutic efficacy of the medicines. In order to synthesize the medicines having high optical purity, the optical purity of the corresponding in termediates should be high. As the optical purity is higher, the price of the compound is even more expensive. Thus, compounds having high optical purity of 99%ee or higher are of great value. [3] Glycidylphthalimide is widely used as an intermediate of medicines, agrochemicals or physiologically active materials. Conventional methods for preparing glycidylph thalimide known in the art are as follows. [4] There was disclosed a method for preparing glycidylphthalimide, comprising reacting phthalimide with epichlorohydrin in a presence of tetra-n-butylammonium iodide and potassium carbonate inside a microwave oven (Synlett, 1996, p873-874). However, the method fails to produce the target compound in a satisfactory yield. [5] There was disclosed another method for preparing glycidylphthalimide by refluxing potassium phthalimide under an epichlorohydrin solvent (J. Org. Chem. 1963, vol. 28, pl589-1593; J. Am. Chem. Soc. 1995, vol. 117, p i 1220-1 1229). However, the method suffers from the disadvantages that optical purity of the glycidylphthalimide decreases due to racemization that takes place during refluxing epihalohydrin in the presence of potassium phthalimide. Further, excessive use of the expensive optically active epi halohydrin as a solvent deteriorates the price competitiveness. [6] There was disclosed a method for preparingglycidylphthalimide by reacting epichlorohydrin with potassium phthalimide in a , -dimethylformaldehyde solvent ( HeIv. Chim. Acta 1990, vol. 73, p912-915). The method reduces the amount of epichlorohydrin to be used. However, when optically active epichlorohydrin (99%ee) reacts with potassium phthalimide in a polar aprotic solvent such as N,N- dimethylamide, selectivity decreases and racemization takes place. Consequently, the resultant glycidylphthalimide has poor optical purity (63%ee), which is not adequate for medicines. [7] As an alterative, there was disclosed a method for preparing optically active gly cidylphthalimide by coupling optically active glycidol with phthalimide in a presence of diethylazodicarboxylate and triphenylphosphine that are Mitsunobu reagents ( TetrahedronAsymmetry, 1996, vol. 7, pl641-1648 and Tetrahedron, 2004, vol. 60, p7679-7692). However, the method has a problem that purification of the resultant optically active glycidylphthalimide is not easy due to the byproducts of the Mitsunobu reactions. Therefore, the method is not applicable to industrial-scale production. [8] Recently, U.S. Patent No. 6,875,875 disclosed a method for preparing glycidylph thalimide by reacting optically active epichlorohydrin with an alkali metal salt of ph thalimide in an alcohol solvent, or by reacting optically active epihalohydrin with ph thalimide in the presence of an inorganic salt (e.g., alkali metal carbonate or alkali metal hydrogencarbonate) or a quaternary ammonium salt to obtain N - (3-halo-2-hydroxypropyl)phthalimide, and then by cyclizing the obtained product with alkali metal alkoxide. According to the method, chiral glycidylphthalimide is obtained in high optical purity of 98%ee. However, the method requires excessive use of the expensive optically active epichlorohydrin in an amount of 3 times or 2 times of the alkali metal phthalimide or phthalimide. Further, in the synthesis of the glycidylph thalimide from -(3-halo-2-hydroxypropyl)phthalimide, some of glycidylphthalimide synthesized undergoes decomposition by the addition of water after completion of the cyclization reaction. In addition, the optical purity of the starting material is somewhat reduced because selectivity is not distinguishable. Accordingly, the resultant gly cidylphthalimide has an optical purity of 98%ee or less. For these reasons, the industrial-scale synthesis of glycidylphthalimide having high optical purity of 98%ee or higher, preferably 99%ee or higher is being demanded. Disclosure of Invention Technical Problem [9] An object of the present invention is to provide a process for the efficient preparation of chiral glycidylphthalimide with high optical purity of 99%ee or higher. The process of the present invention makes it possible to prepare the targeted glycidylphthalimide with an optical purity of 99%ee or higher, while chirality of the starting material is retained. Technical Solution [10] According to a preferred embodiment of the present invention, there is provided a process for the preparation of chiral glycidylphthalimide, which comprises the steps of a) reacting an optically active 3-substituted l-amino-2-propanol acid addition salt with phthalic anhydride in a presence of a base to obtain N - (3-sustituted-2-hydroxypropyl)phthalimide and b) subjecting the obtained compound to an epoxide cyclization reaction to prepare the chiral glycidylphthalimide. [11] According to more preferred embodiment of the present invention, there is provided a process for the preparation of glycidylphthalimide, wherein 3-substituted l-amino-2-propanol acid addition salt is l-amino-3-halo-propanol acid addition salt including l-amino-3-halo-2-propanol hydrochloride salt,
Load more

Recommended publications
  • Synthesis and Characterization of New Derivatives Imides from Metoclopramide
    Turkish Journal of Physiotherapy and Rehabilitation; 32(3) ISSN 2651-4451 | e-ISSN 2651-446X SYNTHESIS AND CHARACTERIZATION OF NEW DERIVATIVES IMIDES FROM METOCLOPRAMIDE Huda Shaker Arif1, Sameaa J. Khamms2 Department of chemistry, College of Science women; University of Baghdad, Baghdad, Iraq [email protected], [email protected] ABSTRACT This study includes synthesis and characterization of new imide derivatives (R or Ar-2-(N-phthalimido acetyl, N-(2-aminoacetyl substituted benzothiazole, via of the reaction from 3-chloro-4-(2-chloroacetamido)- N-(2-(ethyl (methyl) amino) ethyl)-6-methoxycyclohex-1-ene-1-carboxamide with potassium phthalimide or potassium succinimide and substituted-2-aminobenzothiazole. Using absolute ethanol as a solvent. This mixture was refluxed for (6 - 8) hrs. While maintaining the pH at 6. The prepared compounds were characterized by melting point, FT-IR and 1H-NMR spectroscopy Key words: 2-aminobenzothiazole, Derivatives imides, metoclopramide drugs and biological activity. I. INTRODUCTION Metoclopramide (MCP), monohydrate of 4-amino-5- chloro-N-[(2-diethyl amino)ethyl]-2-methoxy benzamide mono hydrochloride (Figure 1) is a substituted benzamide and commonly used as an anti-emetic in the management of some forms of nausea and vomiting and for stimulating the motility of the upper gastrointestinal tract [1][2]. Benzothiazole belongs to the family of bicyclic hetero cyclic compounds having benzene nucleus fused with five - membered ring comprising nitrogen and sulfur atoms[3]. Being a hetero cyclic compound, benzothiazole finds use in research as a starting material synthesis of larger, usually bioactive structures. Its, aromaticity makes it relatively stable; although as aheterocycle, it has reactive sites, which allow for function alization[4][5][6].
    [Show full text]
  • Loba Chemie Pvt
    TABLE OF CONTENT INTRODUCTION Contact US ii MD Letter iii Company Profile iv Latest Information v Label vi Certifications vii GMP Compliant Pharma Facility viii QC Capability ix R&D x Logistic xi COA xii SDS xiii Packing xiv Quality xvi Terms Of Sales xvii Application xviii Product Highlights xix Nanopowder & Carbon Nanotubes xxvii List of New Products xxviii ALPHABETICAL PRODUCT LISTING Price List Chemical 01-155 Ecosafe Safety Products 156-160 Macherey-Nagel Filtration Products 161-181 [email protected] I CONTACT US Contact us for more information on any of our products and services HEAD OFFICE - MUMBAI Loba Chemie Pvt. Ltd., Jehangir Villa, 107, Wode House Road, Colaba, Mumbai-400005 Maharashtra, India Tel: +91(022) 6663 6663 Fax: +91(022) 6663 6699 MANUFACTURING UNIT (TARAPUR) Loba Chemie Pvt. Ltd., Plot No.: D-22, M.I.D.C. Tarapur, Boisar, Taluka: Palghar, Thane-401506 Maharashtra, India Ph: +91(02525) 300 001 Stay up to date about our range and availability www.lobachemie.com Get in touch with us General Enquiry: [email protected] Technical Query: [email protected] Domestic Sales: [email protected] Export Sales: [email protected] Follow us on: ii www.lobachemie.com WELCOME AT LOBA CHEMIE Dear Valued Reader Another exciting year has gone by and we would like to start the New Year, as usual, with a new catalogue featuring more innova- tive highest quality range of routine and novel Laboratory Chemi- cal and Fine Reagents. With our more than 4 decads of expertise in Laboratory Chemical and Fine Reagents we not only bring you a complete Laboratory at your fingertips but in addition with our expertise we have palced our brand of products in a very competitive position for years to come.
    [Show full text]
  • Key Elements of Green Chemistry
    KEY ELEMENTS OF GREEN CHEMISTRY Lucian Lucia North Carolina State University North Carolina State University Key Elements of Green Chemistry Lucian Lucia This text is disseminated via the Open Education Resource (OER) LibreTexts Project (https://LibreTexts.org) and like the hundreds of other texts available within this powerful platform, it freely available for reading, printing and "consuming." Most, but not all, pages in the library have licenses that may allow individuals to make changes, save, and print this book. Carefully consult the applicable license(s) before pursuing such effects. Instructors can adopt existing LibreTexts texts or Remix them to quickly build course-specific resources to meet the needs of their students. Unlike traditional textbooks, LibreTexts’ web based origins allow powerful integration of advanced features and new technologies to support learning. The LibreTexts mission is to unite students, faculty and scholars in a cooperative effort to develop an easy-to-use online platform for the construction, customization, and dissemination of OER content to reduce the burdens of unreasonable textbook costs to our students and society. The LibreTexts project is a multi-institutional collaborative venture to develop the next generation of open-access texts to improve postsecondary education at all levels of higher learning by developing an Open Access Resource environment. The project currently consists of 13 independently operating and interconnected libraries that are constantly being optimized by students, faculty, and outside experts to supplant conventional paper-based books. These free textbook alternatives are organized within a central environment that is both vertically (from advance to basic level) and horizontally (across different fields) integrated.
    [Show full text]
  • Catalog-2016-2017.Pdf
    Catalog # Item Description Structure Pack Rs./Pack ASD2594 198.13, see 3,5-Dinitrobenzyl alcohol Page No 183 ASA2593 ABTS, 98% (Custom work) 30931-67-0 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt F.W. 548.68 POR ASC1136 ACE-Cl, see 1-Chloroethyl chloroformate Page No 117 ASA1617 Acenaphthene, 99% 83-32-9 1,8-Ethylenenaphthalene F.W. 154.2 100 g 400 mp : 92-95°C, bp : 278°C 500 g 1400 d : 1.15 MERCK : 13,29, UN 3077 R : 36/37/38-50/53, S : 26-36/37/39-60-61 ASA1992 Acenaphthenequinone, 95% 82-86-0 F.W. 182.18 25 g 3000 mp : 257-259°C 100 g 11000 R : 36/37/38, S : 26-36 ASA1001 Acetal, see Acetaldehyde diethyl acetal Page No 1 ASA1001 Acetaldehyde diethyl acetal, 97% Acetal Or 1,1-Diethoxyethane F.W. 118.1 25 ml 500 105-57-7 bp : 101-102°C 100 ml 1600 d : 0.831, Fp : -21°C(-6°F) RI : 1.3810, MERCK : 13,39, UN 1088 R : 11-36/38, S : 16-33/9 ASA1002 Acetaldehyde dimethyl acetal, 90% 1,1-Dimethoxyethane Or Dimethyl acetal F.W. 90.1 25 g 1500 534-15-6 bp : 64°C 100 g 2600 d : 0.852, Fp : -17°C(1°F) 500 g 4500 RI : 1.3670, MERCK : 13,3253, UN 2377 R : 11, S : 16-33/9 ASA2477 Acetaldehyde, 20-30% solution 75-07-0 F.W. 44.05 500 ml 400 bp : 20.8 °C 2.5 lt 1900 d : 1.004 5 lt 3500 ASA1003 Acetamide, 98% Amide C2 F.W.
    [Show full text]
  • Wo 2009/128088 A2
    (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date 22 October 2009 (22.10.2009) WO 2009/128088 A2 (51) International Patent Classification: AO, AT, AU, AZ, BA, BB, BG, BH, BR, BW, BY, BZ, COlC 209/62 (2006.01) C07C 311/16 (2006.01) CA, CH, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, (21) International Application Number: HR, HU, ID, IL, IN, IS, JP, KE, KG, KM, KN, KP, KR, PCT/IN2008/000725 KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, MD, ME, (22) International Filing Date: MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, 3 November 2008 (03.1 1.2008) NZ, OM, PG, PH, PL, PT, RO, RS, RU, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TJ, TM, TN, TR, TT, TZ, UA, (25) Filing Language: English UG, US, UZ, VC, VN, ZA, ZM, ZW. (26) Publication Language: English (84) Designated States (unless otherwise indicated, for every (30) Priority Data: kind of regional protection available): ARIPO (BW, GH, 923/CHE/2008 15 April 2008 (15.04.2008) IN GM, KE, LS, MW, MZ, NA, SD, SL, SZ, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, MD, RU, TJ, (71) Applicant (for all designated States except US): SHOD- TM), European (AT, BE, BG, CH, CY, CZ, DE, DK, EE, HANA LABORATORIES LIMITED [IN/IN]; Plot ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LV, No.26, Phase- 1, IDA-Jeedimetla, Andhra Pradesh, Hyder MC, MT, NL, NO, PL, PT, RO, SE, SI, SK, TR), OAPI abad 500 055 (IN).
    [Show full text]
  • Preparation Methods of Methyl-D3-Amine and Salts Thereof
    (19) TZZ 548859A_T (11) EP 2 548 859 A1 (12) EUROPEAN PATENT APPLICATION published in accordance with Art. 153(4) EPC (43) Date of publication: (51) Int Cl.: 23.01.2013 Bulletin 2013/04 C07C 209/34 (2006.01) C07B 59/00 (2006.01) C07C 209/62 (2006.01) C07C 211/03 (2006.01) (21) Application number: 11755686.0 (86) International application number: (22) Date of filing: 17.03.2011 PCT/CN2011/071928 (87) International publication number: WO 2011/113369 (22.09.2011 Gazette 2011/38) (84) Designated Contracting States: • FENG, Weidong AL AT BE BG CH CY CZ DE DK EE ES FI FR GB Kunshan GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO Jiangsu 215300 (CN) PL PT RO RS SE SI SK SM TR • DAI, Xiaojun Kunshan (30) Priority: 18.03.2010 CN 201010127698 Jiangsu 215300 (CN) (71) Applicant: Suzhou Zelgen Biopharmaceutical Co., (74) Representative: Denjean, Eric et al Ltd. Cabinet Laurent & Charras Jiangsu 215300 (CN) "Le Contemporain" 50, Chemin de la Bruyère (72) Inventors: 69574 Dardilly Cedex (FR) • GAO, Xiaoyong Kunshan Jiangsu 215300 (CN) (54) PREPARATION METHODS OF METHYL-D3-AMINE AND SALTS THEREOF (57) Preparation methods of methyl-d3-amine and d3-amine, and optionally, methyl-d3-amine reacts sub- salts thereof are provided, which contain the following sequently with acids to form salts of methyl- d3-amine; or steps: (i) nitromethane is subjected to react with deute- (ii) N-(1,1,1-trideuteriomethyl)phthalimide is subjected to rium oxide in the present of bases and phase-transfer react with acids to form salts of methyl-d3-amine.
    [Show full text]
  • The Pharmaceutical and Chemical Journal, 2019, 6(1):72-83 Research
    The Pharmaceutical and Chemical Journal, 2019, 6(1):72-83 Available online www.tpcj.org ISSN: 2349-7092 Research Article CODEN(USA): PCJHBA Synthesis, Characterization and Potential Anticancer and Antimicrobial Activities of New Phthalamide Derivatives Yaprak Yıldız1, HülyaAkgün1*, Hande Sipahi2, İnci Deniz3, Barkın Berk4 1Yeditepe University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry, Atasehir Istanbul, 34755, Turkey 2Yeditepe University, Faculty of Pharmacy, Department of PharmaceuticalToxicology, Atasehir Istanbul, 34755, Turkey 3Yeditepe University, Faculty of Pharmacy, Department of Pharmaceutical Microbiology, Atasehir Istanbul, 34755, Turkey 4İstanbul Medipol University, School of Pharmacy, Department of Pharmaceutical Chemistry, Beykoz Istanbul, 34810, Turkey Abstract A series of N1,N2-bis [(2-substitutedphenyl)ethyl]phthalamide (compounds 1-10) and 3-nitro-N1, N2-bis [(2-substitutedphenyl)ethyl]phthalamide (compounds 11-20) were synthesized. Their structures and purity were analyzed by IR, 1H-NMR spectra and elemental analysis. The compounds were evaluated for their in vitro cytotoxicity against the MCF7 and Hep3B cancer cell lines. Cytotoxicity screening revealed that N1,N2-bis[2-(2,4- dichlorophenyl)ethyl]phthalamide (compound 5), 3-nitro-N1,N2-bis[2-(2,4-dichlorophenyl) ethyl]phthalamide (compound 15) and 3-nitro-N1,N2-bis[2-(2-fluorophenyl)ethyl]phthalamide (compound 16) had the highest activity. The synthesized compounds were also screened for their antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Among the compounds, N, N’-bis[2-(4- chlorophenyl)ethyl]phthalamide (compound 4), 3-Nitro-N,N’-bis[2-(2-chlorophenyl) ethyl]phthalamide (compound 12), 3-Nitro-N,N’-bis[2-(4-chlorophenyl)ethyl] phthalamide (compound 14), and 3-Nitro-N,N’-bis[2-(2,4- dichlorophenyl)ethyl]phthalamide (compound 15) exhibited good activity.
    [Show full text]
  • Note Protection of Amino Group As N-Phthaly\ De
    Indianlourn al of Chemistry VoI.4 IB , May2002,pp. 1083-1085 Note Protection of amino group as N-phthaly\ de­ an alkyl halide with potassium phthalimide alone or in 8 rivative using microwave irradiation a non-polar solvent , or by heating ami ne with phthalic anhydride in presence of triethyl amine9 or Shushan M Kh adilkar* & Virendra R Madyar with carbethoxythiobenzoic acid 10. After synthetic Applied Organic Chemistry Laboratory, University Department of transformation's phthalyl group can be easily Chemical Technology, University of Mumbai, Matunga, removed by hydrazonolysis using hydrazine hydrate Mumbai 400019, India. Fax 91-022-4145619, to yield amine and phthalyl hydrazide. From the Received 23 November 2000; accepted (revised) 9 October 2001 literature it was seen that the methods available for the preparation of N-(2-hydroxyethyl)phthalimide The amino groups for various substrates are protected as N­ were those described by Giles Ralph et al. II in which phthalyl derivatives usi ng solvent free neat condition under large excess of anhydride to ethanol amine is used, microwave exposure. and this mixture is then heated to high temperature at about ISO°C for 1 hr and vacuum distilled so as to get The selection of an appropriate protective group is an moderate yields of the desired products. In yet another important step in the development of a synthetic l2 method described by Yataro Obata a mixture of K­ methodology. The reports of new protective groupsl pthalimide and l-chloroethanol were heated in a and methods for its protection and cleavage appear sealed tube at 132°C for 6 hr to give the expected regularly in the literature.
    [Show full text]