Melting point	173-176 ºC
Specific optical rotation	168 º (c=1, acetone)

Symbol(GHS)	Xi
Hazard Codes	R36/37/38
SDS/MSDS	S26;S37/39

Source	SDS/MSDS Samples
Alfa-Aesar	View & Download
Sigma-Aldrich	View & Download
TCI	View & Download

Synthetic Route

More

Name	CAS

More

Articles

Peer-Reviewed Papers

Journal of the Chemical Society. Perkin Transactions 1, 263-263 (1993) Organic Syntheses, 69, 220-220 (1990) Squaric acid and esters: analysis for contaminants and stability in solvents.M G Wilkerson et al.Journal of the American Academy of Dermatology, 13(2 Pt 1), 229-234 (1985-08-01) Conjugation of p-aminophenyl glycosides with squaric acid diester to a carrier protein and the use of neoglycoprotein in the histochemical detection of lectins.L F Tietze et al.Bioconjugate chemistry, 2(3), 148-153 (1991-05-01) Squaric acid mediated synthesis and biological activity of a library of linear and hyperbranched poly(glycerol)-protein conjugates.Frederik Wurm et al.Biomacromolecules, 13(4), 1161-1171 (2012-03-02) The Journal of Organic Chemistry, 59, 4707-4707 (1994) Enzymatic glycosylation of reducing oligosaccharides linked to a solid phase or a lipid via a cleavable squarate linker.O Blixt et al.Carbohydrate research, 319(1-4), 80-91 (1999-10-16) Dicyanomethylene Substituted Benzothiazole Squaraines: The Efficiency of Photodynamic Therapy In Vitro and In Vivo.Yongbiao Wei et al.EBioMedicine, 23, 25-33 (2017-08-16) Percutaneous penetration of squaric acid and its esters in hairless mouse and human skin in vitro.E F Sherertz et al.Archives of dermatological research, 280(1), 57-60 (1988-01-01) Recognition of Dimeric Lewis X by Anti-Dimeric Lex Antibody SH2.Sinthuja Jegatheeswaran et al.Vaccines, 8(3) (2020-09-23) Bioisosteric replacement of the alpha-amino carboxylic acid functionality in 2-amino-5-phosphonopentanoic acid yields unique 3,4-diamino-3-cyclobutene-1,2-dione containing NMDA antagonists.W A Kinney et al.Journal of medicinal chemistry, 35(25), 4720-4726 (1992-12-21) The relationship between sensitization with squaric acid diethylester and IgE-mediated allergy.P D Pigatto et al.Bollettino dell'Istituto sieroterapico milanese, 63(3), 226-228 (1984-07-31) Sensitizing potential of cyclobutenediones.J Avalos et al.Contact dermatitis, 21(5), 341-342 (1989-11-01)

Remarks