Your question is ambiguous. When you say "next to all > <something.. >", do you mean the next line like this? 

#! perl -sw
use strict;

m[> <(.*)>] and print "$1: ", scalar <STDIN> while <STDIN>;

__END__
P:\test>perl 330148.pl < 330148.dat
$NAM: (+)-catechin
Formula: C15H14O6
MolWeight: 290.26806
ChemBankID: 1254
CompoundName: (+)-catechin
Calbiochem Catalog: 219250
MicroSource Catalog: 210205
$NAM: (+)-himbacine
Formula: C22H35NO2
MolWeight: 345.51884
ChemBankID: 1861
CompoundName: (+)-himbacine
Calbiochem Catalog: 377200
$NAM: (+)-methamphetamine
Formula: C10H15N
MolWeight: 149.23284
ChemBankID: 1568
CompoundName: (+)-methamphetamine
MicroSource Catalog: 1900033

[download]

Or everything from the > <something> to the next?

If the latter, then you could set $/="\n> <"; and then each read will get you an entire multi-line record. 

#! perl -sw
use strict;

local $/ = "\n> <";

m[([^>]+)>\n(.*)]sm and print "$1\n$2\n---------\n" while <STDIN>;

[download]
results:
P:\test>perl 330148.pl < 330148.dat
$NAM
(+)-catechin

> <
---------
Formula
C15H14O6

> <
---------
MolWeight
290.26806

> <
---------
ChemBankID
1254

> <
---------
CompoundName
(+)-catechin

> <
---------
Calbiochem Catalog
219250

> <
---------
MicroSource Catalog
210205

$$$$
(+)-himbacine
  SMI2MOL

 25 28  0  0  0  0  0  0  0  0999 V2000
    0.0000    0.0000    0.0000 C   0  0  0  0  0  0  0  0
    0.0000    0.0000    0.0000 C   0  0  2  0  0  0  0  0
    0.0000    0.0000    0.0000 C   0  0  1  0  0  0  0  0
  1  2  1  0  0  0  0
  2 25  1  0  0  0  0
 14 25  1  0  0  0  0
M  END
> <
---------
....truncated for posting....

[download]
Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
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Timing (and a little luck) are everything!

In reply to Re: parsing using metacharacters by BrowserUk
in thread parsing using metacharacters by myraja

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