https://webbook.nist.gov/cgi/cbook.cgi?ID=C66680228
3-Methoxy-6,6,8,8-tetramethyl-4,7-dioxa-1,2-diazaspiro[4,4]non-2-ene-1-carboxylic acid, methyl ester
https://pubchem.ncbi.nlm.nih.gov/patent/EP-0359341-B1
1,6-diazaspiro[4,4]nonane-2,7-dione derivatives - Patent EP-0359341-B1 - PubChem
EP-0359341-B1 chemical patent summary.
https://www.mdpi.com/1420-3049/5/12/M177
2-(4-Biphenyl-1-yl)-1,3-diazaspiro[4,5]dec-1-en-4-thione
The title compound was prepared from imidazolinone 1 whose synthesis as well as 1H and 13C NMR spectra were published previously [1].[...]
biphenyl
https://pubchem.ncbi.nlm.nih.gov/compound/7-Benzyl-1-oxa-3_7-diazaspiro_4.5_decane-2_4-dione
7-Benzyl-1-oxa-3,7-diazaspiro[4.5]decane-2,4-dione - PubChem
7-Benzyl-1-oxa-3,7-diazaspiro[4.5]decane-2,4-dione chemical information summary.
https://pubchem.ncbi.nlm.nih.gov/compound/1_1-Dimethylethyl-4-oxa-1_9-diazaspiro_5.5_undecane-9-carboxylate
1,1-Dimethylethyl 4-oxa-1,9-diazaspiro(5.5)undecane-9-carboxylate - PubChem
1,1-Dimethylethyl 4-oxa-1,9-diazaspiro(5.5)undecane-9-carboxylate chemical information summary.
oxapubchem
https://pubchem.ncbi.nlm.nih.gov/compound/5-_2_2-Difluoroethyl_-2_5-diazaspiro_3.4_octane_-bis_trifluoroacetic-acid
5-(2,2-Difluoroethyl)-2,5-diazaspiro[3.4]octane; bis(trifluoroacetic acid) - PubChem
5-(2,2-Difluoroethyl)-2,5-diazaspiro[3.4]octane; bis(trifluoroacetic acid) chemical information summary.
trifluoroacetic acid