Inventor · Neckarsteinach, DE

Erich Fretschner

13Patents
4h-index
13Co-inventors
53Inventor score

Filing activity: Jun 7, 1990 → May 13, 2002

Most-cited inventions

PatentTitleAreaCited byStatus
US4996327A Preparation of pyrazole and its derivatives Chemistry; Metallurgy 7 Expired
US5569769A Preparation of pyrazole and its derivatives Chemistry; Metallurgy 6 Expired
US5744614A Preparation of 3,5-diarylpyrazoles Chemistry; Metallurgy 4 Expired
US5128480A Preparation of 3-methylpyrazole Chemistry; Metallurgy 4 Expired
US5939584A Process for preparing solid, free-flowing water-soluble salts of aryloxy-C.sub.1 -C.sub.4 -alkanecarboxylic acids Human Necessities 4 Expired
US6229022A Method for producing substituted pyrazoles Chemistry; Metallurgy 2 Expired
US6515139B1 Method for producing N-substituted 2-pyrazoline-5-one Human Necessities 1 Expired
US5763659A Preparation of optically active 2-halopropionic acids Chemistry; Metallurgy 0 Expired
US7002023B2 Method for producing 1 substituted 5-chloro-4 methly pyrazoles Chemistry; Metallurgy 0 Expired
US6538135B1 Method for producing 4-amino-5-chloro-1-phenyl pyridazinone-(6) Chemistry; Metallurgy 0 Expired
US5840913A Process for preparing N-substituted pyrazoles Chemistry; Metallurgy 0 Expired
US5847154A Method of preparing 1,2-dimethyl-3,5-diarylpyrazolium methylsulfates Chemistry; Metallurgy 0 Expired
US6252069A Method for the production of 3-isopropyl-1H-2, 1,3-benzothiadiazine-4 (3H)-one-2,2-dioxide Chemistry; Metallurgy 0 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.