PT2168974E - Processo para preparação de drospirenona (6ss,7ss;15ss,16ss-dimetileno-3-oxo-17alfa-pregna-4-eno- 21,17-carbolactona, drsp) - Google Patents

Processo para preparação de drospirenona (6ss,7ss;15ss,16ss-dimetileno-3-oxo-17alfa-pregna-4-eno- 21,17-carbolactona, drsp) Download PDF

Info

Publication number
PT2168974E
PT2168974E PT91000117T PT09100011T PT2168974E PT 2168974 E PT2168974 E PT 2168974E PT 91000117 T PT91000117 T PT 91000117T PT 09100011 T PT09100011 T PT 09100011T PT 2168974 E PT2168974 E PT 2168974E
Authority
PT
Portugal
Prior art keywords
17alpha
dimethylene
carbolactone
oxo
pregn
Prior art date
Application number
PT91000117T
Other languages
English (en)
Inventor
Jörg-Thorsten Mohr
Klaus Nickisch
Original Assignee
Bayer Ip Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=7803224&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=PT2168974(E) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Bayer Ip Gmbh filed Critical Bayer Ip Gmbh
Publication of PT2168974E publication Critical patent/PT2168974E/pt

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07J—STEROIDS
    • C07J53/00—Steroids in which the cyclopenta(a)hydrophenanthrene skeleton has been modified by condensation with a carbocyclic rings or by formation of an additional ring by means of a direct link between two ring carbon atoms, including carboxyclic rings fused to the cyclopenta(a)hydrophenanthrene skeleton are included in this class
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07J—STEROIDS
    • C07J53/00—Steroids in which the cyclopenta(a)hydrophenanthrene skeleton has been modified by condensation with a carbocyclic rings or by formation of an additional ring by means of a direct link between two ring carbon atoms, including carboxyclic rings fused to the cyclopenta(a)hydrophenanthrene skeleton are included in this class
    • C07J53/002—Carbocyclic rings fused
    • C07J53/004—3 membered carbocyclic rings
    • C07J53/007—3 membered carbocyclic rings in position 6-7
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07J—STEROIDS
    • C07J53/00—Steroids in which the cyclopenta(a)hydrophenanthrene skeleton has been modified by condensation with a carbocyclic rings or by formation of an additional ring by means of a direct link between two ring carbon atoms, including carboxyclic rings fused to the cyclopenta(a)hydrophenanthrene skeleton are included in this class
    • C07J53/002—Carbocyclic rings fused
    • C07J53/004—3 membered carbocyclic rings
    • C07J53/008—3 membered carbocyclic rings in position 15/16

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Steroid Compounds (AREA)
  • Heterocyclic Carbon Compounds Containing A Hetero Ring Having Oxygen Or Sulfur (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Pyrane Compounds (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Fats And Perfumes (AREA)
  • Polyesters Or Polycarbonates (AREA)
PT91000117T 1996-08-12 1997-08-11 Processo para preparação de drospirenona (6ss,7ss;15ss,16ss-dimetileno-3-oxo-17alfa-pregna-4-eno- 21,17-carbolactona, drsp) PT2168974E (pt)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19633685A DE19633685C1 (de) 1996-08-12 1996-08-12 Verfahren zur Herstellung von Drospirenon (6beta,7beta;15 beta,16beta-Dimethyl-en-3-oxo-17alpha-pregn-4-en-21,17-carbolacton, DRSP) sowie 7alpha-(3-Hydroxy-1-propyl)-6beta,7beta;15beta, 16beta-dimethylen-5beta-androstan-3beta,5,17beta-triol (ZK 92836) und 6beta,7beta;15beta,16beta-dimethylen-5beta-hydroxy-3-oxo-17alpha-androstan-21,17-carbolacton (90965) als Zwischenprodukte des Verfahrens

Publications (1)

Publication Number Publication Date
PT2168974E true PT2168974E (pt) 2014-08-26

Family

ID=7803224

Family Applications (4)

Application Number Title Priority Date Filing Date
PT01250278T PT1149841E (pt) 1996-08-12 1997-08-11 Processo para a preparação de 6beta,7beta;15beta,16betadimetileno- 5beta-hidroxi-3-oxo-17alfa-androstano-21,17- carbolactona
PT01250277T PT1149840E (pt) 1996-08-12 1997-08-11 Drospirenona (6beta,7beta,15beta,16beta-dimetileno-3-oxo- 17alfa-pregna-4-eno-21,17-carbolactona, drsp) com menos do que 0,2% de impurezas
PT97937562T PT918791E (pt) 1996-08-12 1997-08-11 Processo para a preparacao de drospirenona e de produtos intermediarios para essa preparacao
PT91000117T PT2168974E (pt) 1996-08-12 1997-08-11 Processo para preparação de drospirenona (6ss,7ss;15ss,16ss-dimetileno-3-oxo-17alfa-pregna-4-eno- 21,17-carbolactona, drsp)

Family Applications Before (3)

Application Number Title Priority Date Filing Date
PT01250278T PT1149841E (pt) 1996-08-12 1997-08-11 Processo para a preparação de 6beta,7beta;15beta,16betadimetileno- 5beta-hidroxi-3-oxo-17alfa-androstano-21,17- carbolactona
PT01250277T PT1149840E (pt) 1996-08-12 1997-08-11 Drospirenona (6beta,7beta,15beta,16beta-dimetileno-3-oxo- 17alfa-pregna-4-eno-21,17-carbolactona, drsp) com menos do que 0,2% de impurezas
PT97937562T PT918791E (pt) 1996-08-12 1997-08-11 Processo para a preparacao de drospirenona e de produtos intermediarios para essa preparacao

Country Status (27)

Country Link
US (2) US6121465A (pt)
EP (4) EP1149840B2 (pt)
JP (1) JP3333524B2 (pt)
KR (1) KR100473297B1 (pt)
CN (1) CN1158300C (pt)
AT (3) ATE446966T1 (pt)
AU (1) AU729149B2 (pt)
BG (1) BG62776B1 (pt)
BR (1) BR9711060A (pt)
CA (1) CA2261137C (pt)
CZ (1) CZ297255B6 (pt)
DE (4) DE19633685C1 (pt)
DK (4) DK0918791T3 (pt)
EA (1) EA001947B1 (pt)
ES (4) ES2320626T5 (pt)
HK (1) HK1021190A1 (pt)
HU (1) HU223106B1 (pt)
IL (1) IL127963A (pt)
IS (1) IS2100B (pt)
NZ (1) NZ333697A (pt)
PL (1) PL187474B1 (pt)
PT (4) PT1149841E (pt)
SI (3) SI1149841T1 (pt)
SK (1) SK283546B6 (pt)
TR (1) TR199900262T2 (pt)
UA (1) UA55423C2 (pt)
WO (1) WO1998006738A1 (pt)

Families Citing this family (49)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19633685C1 (de) 1996-08-12 1997-10-09 Schering Ag Verfahren zur Herstellung von Drospirenon (6beta,7beta;15 beta,16beta-Dimethyl-en-3-oxo-17alpha-pregn-4-en-21,17-carbolacton, DRSP) sowie 7alpha-(3-Hydroxy-1-propyl)-6beta,7beta;15beta, 16beta-dimethylen-5beta-androstan-3beta,5,17beta-triol (ZK 92836) und 6beta,7beta;15beta,16beta-dimethylen-5beta-hydroxy-3-oxo-17alpha-androstan-21,17-carbolacton (90965) als Zwischenprodukte des Verfahrens
EP2305267A3 (en) 1999-08-31 2011-08-17 Bayer Schering Pharma Aktiengesellschaft Pharmaceutical combination of ethinylestradiol and drospirenone for use as a contraceptive
US6787531B1 (en) * 1999-08-31 2004-09-07 Schering Ag Pharmaceutical composition for use as a contraceptive
JP4354667B2 (ja) 1999-08-31 2009-10-28 バイエル・シエーリング・ファーマ・アクチエンゲゼルシャフト 避妊薬としての使用へのエチニルエストラジオールとドロスピレノンの医薬用組合せ
US20020132801A1 (en) * 2001-01-11 2002-09-19 Schering Aktiengesellschaft Drospirenone for hormone replacement therapy
DK1611892T3 (da) * 2000-01-18 2009-11-02 Bayer Schering Pharma Ag Farmaceutiske sammensætninger indeholdende drospirenon
WO2003006027A1 (en) 2001-07-13 2003-01-23 Schering Aktiengesellschaft Combination of drospirenone and an estrogen sulphamate for hrt
BR0309780A (pt) 2002-04-26 2005-03-22 Schering Aktiengellschaft Tratamento da hipertensão em mulheres recebendo terapia de reposição hormonal
US7786101B2 (en) * 2002-11-05 2010-08-31 Bayer Schering Pharma Ag Cardiovascular protection using anti-aldosteronic progestins
CL2004000574A1 (es) * 2003-03-21 2005-02-11 Pharmacia Corp Sa Organizada B Proceso para preparar un compuesto 17-espirolactona o la sal de lactona abierta por carbonilacion del correspondiente 17-alquenil o alquinil derivado, los intermediarios que se usan y su proceso de obtencion.
ITMI20040367A1 (it) * 2004-03-01 2004-06-01 Ind Chimica Srl Processo per la preparazione di drospirenone
HUP0402466A2 (en) * 2004-11-30 2006-07-28 Richter Gedeon Vegyeszet Industrial process for preparing 17-hydroxy-6-betha, 7-betha, 15-betha, 16-betha-bis-methylene-3-oxo-17-alpha-pregn-4-ene-21-carboxylic acid gamma lacton and the main, intermediates of the process
HUP0402465A2 (en) * 2004-11-30 2006-07-28 Richter Gedeon Vegyeszet Industrial process for preparing 17-hydroxy-6-betha, 7-betha, 15-betha, 16-betha-bis-methylene-3-oxo-17-alpha-pregn-4-ene-21-carboxylic acid gamma lacton and the main intermediates of the process
DE102004058300B4 (de) * 2004-12-02 2016-09-15 Austriamicrosystems Ag Schaltungsanordnung zur Erzeugung eines komplexen Signals und Verwendung in einem Hochfrequenz-Sender oder -Empfänger
ITMI20042338A1 (it) * 2004-12-06 2005-03-06 Ind Chimica Srl Processo per la preparazione di drospirenone
US7319154B2 (en) 2005-07-21 2008-01-15 Bayer Schering Pharma Ag Process for the production of 3-oxo-pregn-4-ene-21, 17-carbolactones by the metal free oxidation of 17-(3-hydroxypropyl)-3, 17-dihydroxyandrostanes
NZ565247A (en) * 2005-07-21 2011-02-25 Bayer Schering Pharma Ag Process for the production drospirenone utilising the metal-free oxidation of 17-(3-hydroxypropyl)-3,17-dihydroxyandrostanes with TEMPO
SI1746101T2 (sl) * 2005-07-21 2014-09-30 Bayer Pharma Aktiengesellschaft Postopek za pripravo 3-okso-pregn-4-en-21,17-karbolaktonov z oksidacijo 17-(3-hidroksipropil)-3,17-dihidroksiandrostanov brez uporabe kovine
WO2007127266A2 (en) 2006-04-27 2007-11-08 Covidien Ag Electrode pad packaging systems and methods
EP1902711A1 (en) * 2006-09-20 2008-03-26 KAIROSmed GmbH Oral modified release formulations containing Drospirenon and 8-Prenylnaringenin for use in Hormone Replacement Therapy (HRT)
WO2008137050A2 (en) * 2007-05-01 2008-11-13 Sicor Inc. A process for preparing drospirenone and intermediate thereof
DE102007030596B3 (de) * 2007-06-28 2009-03-12 Bayer Schering Pharma Aktiengesellschaft Verfahren zur Herstellung von 17-(3-Hydroxypropyl)-17-hydroxysteroiden
US7960368B2 (en) * 2008-03-05 2011-06-14 Everstra, Inc. Bismethylene-17A carbolactones and related uses
US8222237B2 (en) * 2008-11-25 2012-07-17 Evestra, Inc. Progestational 3-(6,6-ethylene-17B-hydroxy-3-oxo-17A-pregna-4-ene-17A-yl)propionic acid G-lactones
WO2010094623A1 (en) 2009-02-18 2010-08-26 Bayer Schering Pharma Aktiengesellschaft Formulation comprising drospirenone for subcutaneous or intramuscular administration
WO2010094624A1 (en) 2009-02-18 2010-08-26 Bayer Schering Pharma Aktiengesellschaft Particles comprising drospirenone encapsulated in a polymer
US8334375B2 (en) * 2009-04-10 2012-12-18 Evestra, Inc. Methods for the preparation of drospirenone
EP2266998B1 (en) * 2009-06-16 2013-07-24 Crystal Pharma, S.A.U. Process for obtaining 17-spirolactones in steroids
DE102009031909B4 (de) 2009-07-01 2017-02-09 Heyl Chemisch-Pharmazeutische Fabrik Gmbh & Co. Kg Verfahren zur Herstellung von Drospirenon aus Prasteron
WO2011113196A1 (zh) * 2010-03-16 2011-09-22 台州太法药业有限公司 屈螺酮制备方法
CN101830959B (zh) * 2010-05-27 2012-07-18 杭州龙山化工有限公司 一种曲螺酮的合成方法
AR081670A1 (es) 2010-06-29 2012-10-10 Leon Farma Sa Lab Composicion farmaceutica que comprende drospirenona y kit anticonceptivo
US11351122B1 (en) 2010-07-28 2022-06-07 Laboratorios Leon Farma Sa Synthetic progestogens and pharmaceutical compositions comprising the same
US10849857B2 (en) 2010-07-28 2020-12-01 Laboratorios Leon Farma Sa Pharmaceutical compositions comprising active drugs, contraceptive kits comprising active drugs, and methods of administering the same
US9603860B2 (en) 2010-07-28 2017-03-28 Laboratorios Leon Farma Sa Pharmaceutical compositions comprising active drugs, contraceptive kits comprising active drugs, and methods of administering the same
ES2419663T3 (es) 2010-08-03 2013-08-21 Newchem S.P.A. Métodos para la preparación de Drospirenona y productos intermedios de la misma
WO2012107513A1 (en) 2011-02-10 2012-08-16 Crystal Pharma, S.A.U. Process for obtaining drospirenone
ITMI20111383A1 (it) 2011-07-25 2013-01-26 Ind Chimica Srl Processo per la preparazione di drospirenone
KR20140088197A (ko) * 2011-11-04 2014-07-09 바이엘 파마 악티엔게젤샤프트 18-메틸-6,7-메틸렌-3-옥소-17-프레그느-4-엔-21,17β-카르보락톤, 상기 화합물을 함유하는 약제학적 제제 및 자궁내막증 치료에 있어서 이들의 용도
EP2597101A1 (en) 2011-11-22 2013-05-29 Industriale Chimica S.R.L. Process for the preparation of drospirenone
EP2782924B1 (en) 2011-11-22 2016-09-21 Industriale Chimica S.R.L. Process for the preparation of drospirenone
WO2014128525A1 (en) 2013-02-20 2014-08-28 Industriale Chimica S.R.L. Process for the preparation of drospirenone
ES2630331T3 (es) 2013-04-12 2017-08-21 Industriale Chimica S.R.L. Proceso para la preparación de drospirenona
EP3108889A1 (en) 2015-06-23 2016-12-28 Philippe Perrin Drospirenone-based contraceptive for a female patient affected with excess weight
CN108025014B (zh) 2015-06-23 2021-10-22 莱昂实验室制药股份有限公司 用于过重女性患者的基于屈螺酮的避孕药
CN113387993A (zh) * 2021-07-06 2021-09-14 江西百思康瑞药业有限公司 一种屈螺酮的合成方法
EP4134082A1 (en) 2021-08-12 2023-02-15 Chemo Research, S.L. Method for treating endometriosis and providing effective contraception
WO2023152658A1 (en) 2022-02-10 2023-08-17 Lupin Limited Slow release drospirenone tablet composition
WO2023165988A1 (en) 2022-03-01 2023-09-07 Chemo Research, S.L. Chewable oral contraceptive

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2652761C2 (de) * 1976-11-16 1985-11-21 Schering AG, 1000 Berlin und 4709 Bergkamen 15,16-Methylen-Spirolactone, Verfahren zu deren Herstellung und diese enthaltende Arzneimittel
DE3022337A1 (de) * 1980-06-11 1982-01-07 Schering Ag Berlin Und Bergkamen, 1000 Berlin Praeparate zur kontrazeption und zur behandlung gynaekologischer stoerungen
DE3042136A1 (de) * 1980-11-03 1982-06-09 Schering Ag, 1000 Berlin Und 4619 Bergkamen Verfahren zur herstellung von 3 (beta), 7 (beta) -dihydroxy- (delta) (pfeil hoch)5(pfeil hoch) -steroiden
EP0075189B1 (en) * 1981-09-21 1985-08-28 Schering Aktiengesellschaft 3-beta,7-beta,15-alpha-trihydroxy-5-androsten-17-one, its 3,15-dipivalate, and its preparation
DE3414508A1 (de) * 1984-04-13 1985-10-24 Schering AG, 1000 Berlin und 4709 Bergkamen Mehrfach tritiierte steroid-20.17-spirolactone und ihre verwendung als tracersubstanzen
DE3626838A1 (de) * 1986-08-08 1988-02-11 Schering Ag Verfahren zur herstellung von 17(alpha)-pregnan-21,17-carbolactonen
US5106995A (en) * 1989-05-05 1992-04-21 Isp Investments Inc. Production of lactones from diols
DE19633685C1 (de) 1996-08-12 1997-10-09 Schering Ag Verfahren zur Herstellung von Drospirenon (6beta,7beta;15 beta,16beta-Dimethyl-en-3-oxo-17alpha-pregn-4-en-21,17-carbolacton, DRSP) sowie 7alpha-(3-Hydroxy-1-propyl)-6beta,7beta;15beta, 16beta-dimethylen-5beta-androstan-3beta,5,17beta-triol (ZK 92836) und 6beta,7beta;15beta,16beta-dimethylen-5beta-hydroxy-3-oxo-17alpha-androstan-21,17-carbolacton (90965) als Zwischenprodukte des Verfahrens

Also Published As

Publication number Publication date
IL127963A (en) 2004-06-20
DE19633685C1 (de) 1997-10-09
ES2438941T3 (es) 2014-07-21
EP1149841A2 (de) 2001-10-31
DK1149840T5 (da) 2013-09-30
DK1149840T3 (da) 2009-04-27
CA2261137C (en) 2005-03-15
ATE446966T1 (de) 2009-11-15
IL127963A0 (en) 1999-11-30
DK2168974T3 (da) 2014-08-11
EP1149840B2 (de) 2013-05-15
ATE420098T1 (de) 2009-01-15
CZ47099A3 (cs) 1999-05-12
SK283546B6 (sk) 2003-09-11
PL187474B1 (pl) 2004-07-30
SI1149840T2 (sl) 2013-08-30
IS2100B (is) 2006-04-12
DK0918791T3 (da) 2002-07-15
EP1149841A3 (de) 2004-12-01
ES2320626T3 (es) 2009-05-27
US6933395B1 (en) 2005-08-23
JP3333524B2 (ja) 2002-10-15
SI0918791T1 (en) 2002-12-31
AU4014497A (en) 1998-03-06
ES2335860T3 (es) 2010-04-06
EP2168974A2 (de) 2010-03-31
UA55423C2 (uk) 2003-04-15
EP1149840A2 (de) 2001-10-31
DK1149840T4 (da) 2013-07-01
NZ333697A (en) 2000-08-25
DK1149841T3 (da) 2010-03-08
EP1149841B1 (de) 2009-10-28
EP2168974A3 (de) 2013-03-06
CN1223662A (zh) 1999-07-21
TR199900262T2 (xx) 1999-03-22
EA001947B1 (ru) 2001-10-22
CZ297255B6 (cs) 2006-10-11
EP0918791A1 (de) 1999-06-02
CN1158300C (zh) 2004-07-21
BG62776B1 (bg) 2000-07-31
PT1149841E (pt) 2010-01-29
BR9711060A (pt) 1999-08-17
EP0918791B8 (de) 2003-01-08
EA199900153A1 (ru) 1999-06-24
EP1149840A3 (de) 2004-12-01
ES2175451T7 (es) 2012-11-19
WO1998006738A1 (de) 1998-02-19
KR100473297B1 (ko) 2005-03-07
ES2175451T3 (es) 2002-11-16
ES2438941T1 (es) 2014-01-20
DE59713018D1 (de) 2009-12-10
US6121465A (en) 2000-09-19
EP0918791B3 (de) 2012-01-18
BG102976A (en) 1999-08-31
EP2168974B1 (de) 2014-07-02
SI1149841T1 (sl) 2010-02-26
SK19499A3 (en) 1999-10-08
PT918791E (pt) 2002-09-30
AU729149B2 (en) 2001-01-25
KR20000029939A (ko) 2000-05-25
PT1149840E (pt) 2009-03-31
EP0918791B1 (de) 2002-04-03
EP1149840B1 (de) 2009-01-07
SI1149840T1 (sl) 2009-06-30
HU223106B1 (hu) 2004-03-29
HUP9903089A3 (en) 2001-07-30
CA2261137A1 (en) 1998-02-19
ATE215557T1 (de) 2002-04-15
HK1021190A1 (en) 2000-06-02
DE59706887D1 (de) 2002-05-08
PL331530A1 (en) 1999-07-19
ES2320626T5 (es) 2013-09-05
IS4965A (is) 1999-01-29
JP2000516226A (ja) 2000-12-05
DE59712991D1 (de) 2009-02-26

Similar Documents

Publication Publication Date Title
PT2168974E (pt) Processo para preparação de drospirenona (6ss,7ss;15ss,16ss-dimetileno-3-oxo-17alfa-pregna-4-eno- 21,17-carbolactona, drsp)
MX9702308A (es) Composiciones de esterol a partir de jabon de formacion de pulpa.
AU2261901A (en) Processes for preparing clarithromycin polymorphs
CA2384433A1 (en) Novel betulinic acid derivatives having antiangiogenic activity, processes for producing such derivatives and their use for treating tumor associated angiogenesis
HUT74942A (en) New conversion of bisnoralcohol to bisnoraldehyde
MY127864A (en) Improved process for the hydrogenation of maleic acid to 1,4-butanediol
MX9706744A (es) Proceso novedosos para preparar derivados de 2,3-dihidro-benzofuranol.
AU2895797A (en) Carbohydrate derivatives and their solid-phase synthesis
EP0599658A3 (en) Process for the preparation of 6-beta, 14-alpha-dihydroxy-4-androstene-3,17-dione.
MXPA02012053A (es) Procedimiento para la obtencion de 3,3,5-trimetilciclohexanol.
ZA957059B (en) Improved process for the conversion of substituted steroidal 3-halogen-3,5-diene derivatives to substituted steroidal 3,5-diene-3-carboxylic acid derivatives
ZA994944B (en) Catalyst for the hydrogenation of maleic acid to 1,4 butanediol.
IL138501A0 (en) A CONVERGENT SYNTHESIS OF α-ARYL-β-KETONITRILES
AU6684500A (en) Novel c-19-halogen-substituted steroids of the androst-9(11)-ene-series, methodsfor the production and use thereof
AU2024497A (en) Cycloalkyl derivatives and the solid-phase synthesis of such derivatives
ZA967069B (en) Pyridazin-3-one derivatives, their use, and intermediates for their production.
SG84543A1 (en) Improved catalysts for the hydrogenation of maleic acid to 1,4-butanediol