Eisai Chemical Co., Ltd.
22Patents
0Active
22Granted
29Portfolio score
Filing activity: May 19, 1987 → Sep 25, 1997
Most-cited patents
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5547580A | Purification method of crude product | Performing Operations; Transporting | 19 | Expired |
| US4906411A | Process for producing 2-methyl-1,4-naphthoquinone | Chemistry; Metallurgy | 9 | Expired |
| US5216151A | Process for producing benzylphthalazinone derivatives and salts thereof | Human Necessities | 6 | Expired |
| US5557002A | Process for the preparation of biphenyl containing intermediates useful in making angiotensin II receptor antagonists | Emerging Cross-Sectional Technologies | 6 | Expired |
| US5428173A | Process for the preparation of aminothiadiazolylacetyl halide derivtives | Emerging Cross-Sectional Technologies | 3 | Expired |
| US5637716A | Processes for the preparation of hydroquinone and benzoquinone derivatives | Chemistry; Metallurgy | 2 | Expired |
| US5998611A | Process for producing cephem compounds in an aqueous medium | Chemistry; Metallurgy | 2 | Expired |
| US5874611A | Butenyl hydroquinone derivatives | Human Necessities | 2 | Expired |
| US5476955A | Process for the preparation of a quinone derivative | Chemistry; Metallurgy | 1 | Expired |
| US5677471A | Process for the preparation of quinone derivative | Chemistry; Metallurgy | 1 | Expired |
| US5412124A | Preparation process of naphthoquinone derivative and intermediate for the preparation thereof | Chemistry; Metallurgy | 1 | Expired |
| US5631378A | Protected aminothiazolylacetic acid derivatives | Emerging Cross-Sectional Technologies | 1 | Expired |
| US5608092A | 1,4,4.sub.a 5,8,9.sub.a -hexahydro-1.alpha.,4.alpha.-methanoan-thraquinone derivative(s) | Chemistry; Metallurgy | 1 | Expired |
| US5686635A | Tetrahydro-alkenyl-methanonaphthalene-5,8-dione derivatives | Chemistry; Metallurgy | 0 | Expired |
| US5559236A | Intermediates for substituted biphenylmethylmidazopyridine angiotensin II antagonists | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5700938A | Intermediates for imidazopyridine derivatives | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5608068A | Process for the preparation of imidazopyridine derivatives and intermediates | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5650518A | Protected aminothiazolylacetic acid derivatives | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5665888A | Protected aminothiazolylacetic acid derivatives | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5565586A | Oxidative process for the preparation of allyl quinone derivatives | Human Necessities | 0 | Expired |
| US5587504A | Sulfonyloxy-biphenylcarboxylic ester derivatives which are intermediates | Emerging Cross-Sectional Technologies | 0 | Expired |
| US5618969A | Intermediates for imidazopyridines | Emerging Cross-Sectional Technologies | 0 | Expired |
Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.