On TLC the compound have yellow- green color in day light and yellow fluorescence at UV light 365 nm. Its Rf =0.4.mobile phase (toluene:ethylacetate:formic acid)5:4:1, silica gel is stationary phase
There isn't enough information here to make any suggestions.The number of compounds that might have such properties is essentially unlimited. Are we talking about a pure compound or a mixture? What is the source of the compound? The UV absorbance measurement is not helpful because the absorbance depends on the concentration, which we don't know, and we don't know whether 275 nm is the peak of the spectrum. The complete UV-VIS spectrum might be helpful. The molar extinction coefficient might also be useful. Other analytical tools should be applied if the compound is fairly pure, especially IR, NMR, and mass spectrometry or GC-MS.
There isn't enough information here to make any suggestions.The number of compounds that might have such properties is essentially unlimited. Are we talking about a pure compound or a mixture? What is the source of the compound? The UV absorbance measurement is not helpful because the absorbance depends on the concentration, which we don't know, and we don't know whether 275 nm is the peak of the spectrum. The complete UV-VIS spectrum might be helpful. The molar extinction coefficient might also be useful. Other analytical tools should be applied if the compound is fairly pure, especially IR, NMR, and mass spectrometry or GC-MS.
Is the 275 a maximum or is it just some wavelength you measured it at? Show the whole spectrum (if is it yellow, it must absorb somewhere around 450 as well).
The value of absorbance is useless, unless you provide concentration, which you probably do not know, if you do not know the compound. But at least weight concentration could help a little (i.e. mg/ml).
The retention factor says nothing without conditions (stationary phase, mobile phase).
It would be crucial to determine the molecular weight. If could you perform MS analysis, that may give you also some hint on the structure in case of partial fragmentation.
If you do not have access to any of such machines, than basic organic analysis will have to be performed.