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                                                                    EXHIBIT 10.6


                   AMENDMENT NO. 1 TO STOCK PURCHASE AGREEMENT

         AMENDMENT NO. 1 dated April 25, 2001 ("AMENDMENT NO. 1") to STOCK
PURCHASE AGREEMENT dated February 8, 2001, among GBI CAPITAL MANAGEMENT CORP.,
NEW VALLEY CORPORATION, LADENBURG, THALMANN GROUP INC., BERLINER
EFFEKTENGESELLSCHAFT AG and LADENBURG, THALMANN & CO., INC. ("STOCK PURCHASE
AGREEMENT").


         WHEREAS, the Parties have entered into the Stock Purchase Agreement and
desire to amend it in certain respects as set forth herein (capitalized terms
used herein that are defined in the Stock Purchase Agreement shall have the same
meanings herein as in the Stock Purchase Agreement);

         IT IS AGREED:

         1. Section 2.4 of the Stock Purchase Agreement is hereby amended in its
entirety to read as follows:

                  2.4 NET WORTH ADJUSTMENT.

                  (a) As used in this Section 2.4:

                           (i) "PURCHASE PRICE ADJUSTMENT PERCENTAGE" means the
amount (expressed as a decimal) obtained by dividing the Net Closing Book
Differential by $21,263,080.

                           (ii) "NET CLOSING BOOK DIFFERENTIAL" means the amount
obtained by subtracting the Ladenburg Book Differential from the GBI Book
Differential.

                           (iii) "GBI BOOK DIFFERENTIAL" means the amount
obtained by subtracting the Adjusted Total Stockholders' Equity of the Purchaser
on the last day of the calendar month immediately preceding the month in which
the Closing occurs from $21,263,080.

                           (iv) "LADENBURG BOOK DIFFERENTIAL" means the amount
obtained by subtracting the Total Ownership Equity of Ladenburg on the last day
of the calendar month immediately preceding the month in which the Closing
occurs from $29,642,000.

                           (v) "ADJUSTED TOTAL STOCKHOLDERS' EQUITY" means the
amount obtained by taking the sum of (1) the stockholders' equity of the
Purchaser as of the last day of the calendar month immediately preceding the
month in which the Closing occurs, based in part on the Total Ownership Equity
of the Purchaser's subsidiary, GBI Capital Partners Inc. ("GBICP"), and (2) all
out-of-pocket expenses incurred through such date by the Purchaser in connection
with the Stock Purchase Agreement and the related transactions to the extent
such expenses reduce the Purchaser's stockholders' equity.

                           (vi) "TOTAL OWNERSHIP EQUITY" means the amount
referred to as "total ownership equity" in the Focus Reports referred to in
subparagraph (b) below.

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                  (b) Promptly after the Closing, upon filing of Focus Reports
by Ladenburg and GBICP for the calendar month immediately preceding the month in
which the Closing occurs, the individuals then serving as the chief financial
officers of Ladenburg and Purchaser shall cooperate with each other to calculate
the Purchase Price Adjustment Percentage. The Focus Reports for Ladenburg and
GBICP shall be prepared, and the stockholders' equity of the Purchaser shall be
determined, in accordance with GAAP, applied consistently as in the Financial
Statements and the Purchaser Financial Statements. Upon completion of the
calculation of the Purchase Price Adjustment Percentage, the number of shares to
be issued to the Sellers and the conversion price of the Notes to be issued to
the Sellers shall be adjusted (the "Issuance Adjustment") as follows:

                           (i) The number of shares of Purchaser Common Stock to
be issued to the Sellers shall be increased from 18,181,818 to the Total New
Shares and the Purchaser shall issue to the Sellers certificates representing
the Total New Shares less 18,181,818. "Total New Shares" shall mean the quotient
obtained by taking (x) a numerator of 25,000,000 over (y) a denominator of (1)
1.375 less (2) the product of 1.375 and the Purchase Price Adjustment
Percentage. Notwithstanding the foregoing, if the issuance to LTGI of any
additional shares of Purchaser Common Stock pursuant to this Amendment No. 1
shall, when taken together with all other shares of Purchaser Common Stock
issued to LTGI as part of the Purchase Price, require compliance with the
notification provisions of the Hart-Scott-Rodino Antitrust Improvements Act of
1976, as amended (the "HSR ACT"), the Purchaser shall issue to LTGI only that
number of shares of Purchaser Common Stock as shall not require such compliance
and the Purchaser shall not be obligated to issue any further additional shares
of Purchaser Common Stock to LTGI until such compliance has been effected.

                           (ii) The Notes to be issued to the Sellers shall be
amended, a copy of which is annexed hereto as Exhibit A, such that the
conversion price shall be decreased by the amount obtained by taking the product
of $2.60 and the Purchase Price Adjustment Percentage. Notwithstanding the
foregoing, the conversion price of the Notes may not be decreased below a price
that would result in the total number of additional shares of Purchaser Common
Stock being issuable upon conversion of the Notes as a result of such
adjustment, when added to the additional number of shares of Purchaser Common
Stock being issued to the Sellers under subsection (i) above, exceeding 80% of
the sum of (x) the number of additional shares to be issued and issuable to the
Sellers under this Section 2.4(b) and (y) the number of additional shares of
Purchaser Common Stock issuable to Frost-Nevada, Limited Partnership ("Frost")
as a result of the Conversion Price Adjustment (as such term is defined in the
Loan Agreement, dated as of February 8, 2001, as amended on the date hereof,
between the Purchaser and Frost).

                  (c) Upon completion of calculating the Purchase Price
Adjustment Percentage and the Issuance Adjustment, such calculations shall be
submitted to the Enforcement Committee, New Valley and Berliner and shall be
deemed conclusively accepted unless written objection thereto is given by any
Party to the other Parties within 30 days after submission.

                  (d) If, within the 30-day period specified in SECTION 2.4(c),
an objection is made, the Purchaser's Accountants and the Sellers' Accountants
shall jointly review the

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determination of the Purchase Price Adjustment Percentage and the Issuance
Adjustment (the "INITIAL DETERMINATION") and attempt to reach a mutually
satisfactory determination of the Purchase Price Adjustment Percentage and the
Issuance Adjustment. If the Purchaser's Accountants and the Sellers' Accountants
are unable to reach such a mutually satisfactory determination within 30 days
after the Initial Determination has been submitted to them for their joint
review, they shall promptly submit the Initial Determination to a firm of
independent accountants jointly selected by them. The independent third firm
shall submit its determination of the Purchase Price Adjustment Percentage and
the Issuance Adjustment to New Valley, Berliner and the Enforcement Committee
within 30 days of its receipt of the Initial Determination, and the
determination of the Purchase Price Adjustment Percentage and the Issuance
Adjustment by such third firm shall be final and conclusive upon the Parties.
The Purchaser shall pay the fees and expenses of the Purchaser's Accountants and
New Valley and Berliner shall pay the fees and expenses of the Sellers'
Accountants. The fees and expenses of any independent third firm shall be paid
50% by the Purchaser and 50% by New Valley and Berliner.

                  (e) The Purchaser shall issue all shares of Purchaser Common
Stock under this Section 2.4 in the proportion of 80.1% to LTGI and 19.9% to
Berliner. Any additional shares of Purchaser Common Stock to be issued to the
Sellers shall constitute consideration to the Sellers for the LTI Stock
additional to the Purchase Price.

         2. Promptly after the Closing, the Purchaser shall reimburse the
Sellers for all of their out-of-pocket expenses incurred through the date of the
Closing in connection with the Stock Purchase Agreement and the related
transactions.

         3. Section 6.1(a) of the Stock Purchase Agreement and Schedules 3.3,
3.12 and 4.5 thereto are hereby amended to delete all references thereto to the
receipt of approval or consent of AMEX and NYSE and no Party's obligations to
consummate the transactions contemplated by the Stock Purchase Agreement shall
be subject to the receipt of such approval or consent.

         4. Sections 6.2(e), 6.3(b) and 6.3(d) of the Stock Purchase Agreement
are hereby deleted in their entirety.

         5. Schedules 2.8(a) and 2.8(b) are hereby replaced by the attached
Schedules 2.8(a)(i) and 2.8(b)(i) to reflect the directors and officers of the
Purchaser and of GBICP effective as of the Closing Date.

         6. Section 3.9(e) of the Stock Purchase Agreement is hereby amended to
change the reference therein from "90 days" to "180 days."

         7. The Purchaser represents and warrants to the Selling Parties as
follows:

                  7.1 AUTHORITY AND CORPORATE ACTION. Other than the Stockholder
Approval, the Purchaser has all necessary corporate power and authority to enter
into this Amendment No. 1 and such other instruments to be executed and
delivered by the Purchaser in connection with the transactions contemplated by
this Amendment No. 1 ("ADDITIONAL PURCHASER TRANSACTION DOCUMENTS") and to

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consummate the transactions contemplated thereby. Other than the Stockholder
Approval, all corporate action necessary to be taken by the Purchaser to
authorize the execution, delivery and performance of the Additional Purchaser
Transaction Documents has been, duly and validly taken. Each Additional
Purchaser Transaction Document constitutes, or will constitute upon execution
and delivery thereof, the valid, binding and enforceable obligation of the
Purchaser, enforceable in accordance with its terms, except (i) as
enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium, fraudulent transfer or similar laws of general
application now or hereafter in effect affecting the rights and remedies of
creditors and by general principles of equity (regardless of whether enforcement
is sought in a proceeding at law or in equity) and (ii) as enforceability of any
indemnification provision may be limited by federal and state securities laws
and public policy.

                  7.2 CAPITALIZATION. Any additional shares of Purchaser Common
Stock to be issued pursuant to the revised Section 2.4 set forth above will be,
upon issuance in accordance with the terms of this Amendment No. 1, duly
authorized, validly issued, fully paid and nonassessable.

                  7.3 OPINION OF FINANCIAL ADVISOR. The Purchaser has received a
new opinion of Roth Capital Partners, LLC, dated April 24, 2001, to the effect
that the consideration to be paid by the Purchaser for the Ladenburg Stock, as
set forth in the Stock Purchase Agreement as amended hereby, is fair from a
financial point of view to the Purchaser, and a true and complete copy of such
opinion has been delivered to the New Valley Parties and Berliner prior to the
execution of this Amendment No. 1.

         8. The New Valley Companies, on the one hand, and Berliner, on the
other hand, severally and not jointly represent and warrant to the Purchaser as
follows:

                  8.1 AUTHORITY AND CORPORATE ACTION. Such Selling Party has all
necessary corporate power and authority to enter into this Amendment No. 1 and
the other instruments and agreements to be executed and delivered by such
Selling Party in connection with the transactions contemplated by this Amendment
No. 1 (collectively, the "ADDITIONAL SELLER TRANSACTION DOCUMENTS") and to
consummate the transactions contemplated thereby. All corporate action necessary
to be taken by such Selling Party to authorize the execution, delivery and
performance of the Additional Seller Transaction Documents has or will at
Closing have been duly and validly taken. Each of the Additional Seller
Transaction Documents to which it is a party constitutes, or upon the execution
and delivery by such Selling Party will constitute, the valid, binding and
enforceable obligation of such Selling Party, enforceable in accordance with its
terms, except (i) as enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium, fraudulent transfer or similar laws of
general application now or hereafter in effect affecting the rights and remedies
of creditors and by general principles of equity (regardless of whether
enforcement is sought in a proceeding at law or in equity) and (ii) as
enforceability of any indemnification provision may be limited by federal and
state securities laws and public policy.

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         9. COVENANTS.

                  9.1 PROXY STATEMENT.

                           9.1.1 The Purchaser will prepare and file with the
Commission as soon as reasonably practicable after the date of execution of this
Amendment No. 1 a supplement ("Supplement") to the Purchaser's proxy statement,
dated March 28, 2001, under the 1934 Act with respect to the matters addressed
herein. The Purchaser shall give New Valley and Berliner and their counsel the
opportunity to review the Supplement prior to filing it with, or sending it to,
the Commission. The Purchaser will use its best efforts, after consultation with
the other Parties, to cause the Supplement to be mailed to the holders of
Purchaser Common Stock entitled to vote at the Purchaser Stockholder Meeting at
the earliest practicable time.

                           9.1.2 The Purchaser, acting through its Board of
Directors, shall include in the Supplement the recommendation of its Board of
Directors that the stockholders of the Purchaser vote in favor of the matters
presented in the Supplement for approval by vote of the stockholders and shall
otherwise use its reasonable best efforts to obtain the Stockholder Approval.

                  9.2 STOCKHOLDER MEETING. The Purchaser shall cause the
Purchaser Stockholder Meeting to be duly called and held as soon as reasonably
practicable after the date of execution of this Amendment No. 1 for the purposes
of voting on the items previously called for under the Stock Purchase Agreement
as well as the issuance of any additional shares of Purchaser Common Stock to be
issued pursuant to the revised Section 2.4 set forth above in this Amendment No.
1.

                  9.3 ADDITIONAL AGREEMENTS. Concurrently with the execution of
this Amendment No. 1, the Purchaser, GBICP and David Thalheim are executing and
delivering an Amendment No. 2 to the Employment Agreement between GBICP and
David Thalheim, providing for the resignation of Mr. Thalheim's from GBICP
effective at the Closing.

         10. MISCELLANEOUS.

                  10.1 PRESS RELEASE; PUBLIC ANNOUNCEMENTS; FILINGS. Promptly
after execution of this Amendment No. 1, the Parties shall issue a press release
in the form of EXHIBIT A annexed hereto (the "AMENDING RELEASE"). The Purchaser
and New Valley shall also each file with the Commission a Report on Form 8-K/A
with respect to the transactions contemplated hereby (the "8-K/AS" and together
with the Amending Release, the "AGREED ADDITIONAL DISCLOSURE"). Each 8-K/A shall
be provided by its preparer to the other Party prior to filing and the other
Party shall be given a reasonable opportunity to comment thereon. The Parties
shall not make any other public announcements in respect of this Amendment No. 1
or the transactions contemplated herein inconsistent with the Agreed Additional
Disclosure without prior consultation and approval as to the form and content
thereof except to the extent required by law. Notwithstanding the foregoing, a
Party may make any disclosure which its counsel advises is required by
applicable law or regulation, in which case the other Party shall be given such
reasonable advance notice as is practicable in the circumstances and the Parties
shall use their best efforts to cause a mutually agreeable release or
announcement to be issued. The Parties may also make appropriate disclosure of
the transactions contemplated by this Amendment No. 1 to their officers,
directors and Representatives.

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                  10.2 HEADINGS. The headings contained in this Amendment No. 1
are for reference purposes only and shall not affect in any way the meaning or
interpretation of this Amendment No. 1.

                  10.3 SEVERABILITY, ETC. As amended hereby, the Stock Purchase
Agreement shall continue in full force and effect. All references in the Stock
Purchase Agreement to the term "Agreement" shall hereafter mean the Stock
Purchase Agreement as amended hereby. If any term or other provision of this
Amendment No. 1 is invalid, illegal or incapable of being enforced by any rule
of law or public policy, all other conditions and provisions of this Amendment
No. 1 shall nevertheless remain in full force and effect so long as the economic
or legal substance of the transactions contemplated hereby is not affected in
any manner materially adverse to any Party.

                  10.4 GOVERNING LAW. This Agreement shall be governed by, and
construed in accordance with, the law of the State of New York without giving
effect to principles of conflicts of law.

                  10.5 COUNTERPARTS. This Amendment No. 1 may be signed in any
number of counterparts, each of which shall be an original, with the same effect
as if the signatures thereto were upon the same instrument. Delivery of an
executed counterpart of a signature page of this Amendment No. 1 by telecopier
shall be effective as delivery of a manually executed counterpart of this
Amendment No. 1.

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         IN WITNESS WHEREOF, the Parties have caused this Amendment No. 1 to the
Stock Purchase Agreement to be executed as of the date first written above.

                                         GBI CAPITAL MANAGEMENT CORP.



                                         By:  /s/ RICHARD J. ROSENSTOCK
                                             --------------------------------
                                             Name: Richard J. Rosenstock
                                             Title: President


                                         NEW VALLEY CORPORATION



                                         By:  /s/ Richard J. Lampen
                                             ----------------------------------
                                             Name: Richard J. Lampen
                                             Title: Executive Vice President


                                         BERLINER EFFEKTENGESELLSCHAFT AG



                                         By:  /s/ Holger Timm
                                             -----------------------------------
                                             Name: Holger Timm
                                             Title: Chief Executive Officer


                                         LADENBURG, THALMANN GROUP INC.



                                         By:  /s/ Victor M. Rivas
                                             ----------------------------------
                                             Name: Victor M. Rivas
                                             Title: Chairman and Chief Executive
                                                    Officer


                                         LADENBURG, THALMANN & CO. INC.



                                         By:  /s/ Victor M. Rivas
                                             ----------------------------------
                                             Name: Victor M. Rivas
                                             Title: Chairman and Chief Executive
                                                    Officer

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