load=1ksx
select *:c or *:g or *:a or *:b or *:e or *:f
restrict selected
cartoon on

define rib_pol *.O?' and dna
define rib_not *.C?' and dna
define ph_pol *.OP? and dna
define ph_not *.P and dna
define big_pol (da and (*.N6 or *.N7)) or (dc and *.N4) or (dt and *.O4) or (dg and (*.N7 or *.O6))
define big_not (da and (*.C5 or *.C6)) or (dc and (*.C4 or *.C5 or *.C6)) or (dt and (*.C4 or *.C5 or *.C6)) or (dg and (*.C8 or *.C5 or *.C6))
define smal_pol (da and (*.N3 or *.N9)) or (dc and (*.O2 or *.N1)) or (dt and (*.N1 or *.O2)) or (dg and (*.N9 or *.N3 or *.N2))
define smal_not (da and (*.C2 or *.C4)) or (dc and *.C2) or (dt and (*.C2 or *.C6)) or (dg and (*.C4 or *.C2))

define prot_pol protein and (nitrogen or oxygen)
define prot_not protein and (carbon or sulfur)

select within (3.5, rib_pol) and prot_pol
select within (4.5, rib_not) and prot_not

select within (3.5, ph_pol) and prot_pol
select within (4.5, ph_not) and prot_not

select within (3.5, big_pol) and prot_pol
select within (4.5, big_not) and prot_not

select within (3.5, smal_pol) and prot_pol
select within (4.5, smal_not) and prot_not